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Introduction: Developmental dyslexia is usually defined as a significant difficulty in reading, writing and spelling despite normal intellectual capacity and educational resources, adequate socio-cultural opportunity and in the absence of macroscopical acquired lesions. Given the complexity of cognitive processes involved in reading, a wide range of possible explanations have been suggested for dyslexia, such as (A) a specific linguistic problem due to a deficit in phonological processing (1-3); (B) an impairment of the magnocellular pathway (4-5) (C) a deficit of the cerebellar system (6-8). Each of these theories has found support in behavioural and/or imaging experiments. However, the majority of these studies have investigated only one explanatory variable on the same sample of dyslexics (1-8). Recently, multiple single-case studies have been performed to assess to what extent phonological, magnocellular and cerebellar deficits co-exist in the same sample of dyslexic subjects. Ramus and collegues (2) concluded that dyslexia is best explained by the presence of a phonological deficit. On the contrary, Reid and collegues (9) concluded that different sub-types of developmental dyslexia with different underlying causes may exist. However, these studies lack explicit testing of some of the hypotheses which are anatomical in nature (e.g. the cerebellar hypothesis). The aim of this study was therefore to re-assess the co-morbidity issue in dyslexia in the same sample of subjects using both behavioural and imaging indexes to challenge the three aforementioned hypotheses. Methods: 23 right-handed controls and 8 right-handed subjects with diagnose of dyslexia participated in the study. The two groups were matched for age, education and I.Q. Before scanning, in all subjects, we assessed reading and behavioural tasks to evaluate reading ability, phonological skills, auditory and visual magnocellular skills and motor-cerebellar skills. During fMRI session, subjects performed 4 tasks: non-word reading, auditory rhyming task (phonological task), movement detection of a high spatial frequency stimulus (magnocellular task) and a motor sequence learning task (motor task known to involve the cerebellum). Each task corresponded to an fMRI session that involved 60 fMRI scans. A block design was used. Simple effects and comparisons between dyslexics and controls were computed for each task. Behavioural results: There was a significant between-group difference for words and non-words reading, spoonerism task, stress assigment task, digit naming and sentence dictation. However, the single-subject analyses showed that reduced performance in reading and in phonological tasks was occasionally associated with a reduced performance in tasks designed to test magnocellular visual or the motor “cerebellar” systems. fMRI results: No significant between-group differences emerged from the analyses of the behavioural data during fMRI scans. Normal controls showed the well known pattern of left hemisphere activation for reading, in the inferior frontal gyrus, in the temporo-parietal areas and in ventral occipito-temporal areas. Dyslexics showed reduced activation in the left inferior frontal gyrus and in the left temporal and occipito-temporal areas for non-word reading, a task where dyslexics are slower than controls when tested in time constrained protocols outside the scanner. However, the dyslexics also had reduced activations for tasks in which they did not show systematic behavioural deficits. In particular, in the left anterior occipito-temporal cortex for the simple rhyming task adopted here, in the right posterior occipitotemporal region for motion detection, and in the cerebellum for the motor learning task. Discussion: Although at the behavioural level, the vast majority of the dyslexic subjects did not show a reduced performance in “magnocellular” and motor tasks, functional data showed physiological deficits that involved all systems under investigation (phonological, visual magnocellular and motor-cerebellar systems). On the basis of these results we propose that a disorder of phonological, magnocellular and cerebellar systems co-occurs in developmental dyslexia. However, the phonological deficit together with the reading speed deficit stands above other difficulties being evident at both behavioral and physiological level.Bibliography 1. Frith U. (1999) Dyslexia 5(4): 192-214. 2. Ramus F. (2003) Curr Opin Neurobiol 13(2): 212-8. 3. Snowling M.J. (2001) Dyslexia 7(1): 37-46. 4. Stein J. and Walsh V. (1997) Trends Neurosci 20(4): 147-52. 5. Demb J.B. et al. (1998) J Neurosci 18(17): 6939-51. 6. Nicolson R.I. and Fawcett A.J.(1990) Cognition 35(2): 159-82. 7. Nicolson R. I., Fawcett A. J., et al. (1999) Lancet 353(9165): 1662-7. 8. Nicolson R. I., Fawcett A. J., et al. (2001) Trends Neurosci 24(9): 508-11. 9. Reid A., Szczerbinski M., et al. (2007) Dyslexia 13(1): 1-24.

BACKGROUND AND PURPOSE: Endovascular treatment (EVT) of carotid cavernous fistulas (CCFs) is based on various techniques, mainly those using detachable balloons. Coronary covered stent grafts have been sporadically used in the intracranial arteries and only 2 traumatic CCFs have been reported in the literature; moreover, there is poor information about the long-term follow-up. We present 8 cases of CCFs treated by the placement of a covered stent, 5 of which have a 1-year clinical and angiographic follow-up. METHODS: Eight patients with posttraumatic CCF were treated by positioning a covered stent in the intracranial internal carotid artery (ICA) to occlude the fistula. They received periodic clinical and angiographic follow-up to evaluate the patency and the stability of clinical results. RESULTS: In all cases, the symptoms related to the CCF regressed after treatment and did not recur in the follow-up. Two patients presented residual filling of the CCF at the end of the procedure. The angiographic follow-up revealed in 6 patients of 7 a good patency of the ICA; in 1 patient, there was an ICA asymptomatic occlusion. One patient required transvenous coil occlusion of the cavernous sinus. CONCLUSION: When standard treatments fail, covered stent grafts can be used as a valid alternative in the treatment of CCFs, but more data are needed, especially in the long-term follow-up.

In ischaemic stroke, thrombolytic drugs speed the recanalisation of intracerebral arteries. The effects of aspirin are not known. A trial was conducted to determine whether, separately or together, streptokinase and aspirin have clinical benefits in acute ischaemic stroke similar to those in acute myocardial infarction. 622 patients with acute ischaemic stroke within 6 hours of symptom onset were randomised with a 2x2 factorial design to (i) a 1-hour intravenous infusion of 1 . 5 MU streptokinase, (ii) 300 mg/day buffered aspirin for 10 days, (iii) both active treatments, or (iv) neither. Early results raised a question whether the trial should be continued. Streptokinase (alone or with aspirin) was associated with an excess of 10-day case fatality (odds ratio 2 . 7; 95% confidence interval 1 . 7-4 . 3; 2p

BACKGROUND: Left caloric vestibular stimulation (CVS) transiently reduces impairments of right-brain-damaged patients with left unilateral neglect, including left hemianesthesia, contralateral to the side of the lesion (contralesional). Conversely, no effect on right contralesional hemianesthesia in left-brain-damaged patients is seen with right CVS. This discrepancy is unexplained. METHODS: The authors explored the effect of CVS on right- and left-brain-damaged patients with hemianesthesia. One left-brain-damaged patient had an fMRI study during tactile stimulation before and after left CVS. The same fMRI touch study, without CVS, was performed in neurologically unimpaired subjects. RESULTS: A transient remission of right hemianesthesia associated with left brain damage was observed, provided that cold CVS was administered to the left ear. In the left-brain-damaged patient studied with fMRI, left CVS modulated the neural response to right hand tactile stimuli of a portion of the secondary somatosensory area (SII) of the right hemisphere. In neurologically unimpaired subjects, fMRI scans showed that the same part of area SII in the right hemisphere was activated by ipsilateral right-sided touches and to a larger extent than area SII in the left hemisphere by left-sided touches. CONCLUSIONS: Left caloric vestibular stimulation is effective on both left and right hemianesthesia because it modulates the hemisphere that has a more complete representation of, or is capable to attend to, the whole somatosensory surface of the body. These results suggest a hardwired hemispheric asymmetry in hand representation, starting from a somatotopically organized brain region such as area SII.

In this paper we review the clinical and morphological results of intracranial aneurysms treated with Guglielmi Detachable Coils.We report our experience in 100 patients with intracranial aneurysms treated with GDC. Since February 1993 we have treated 70 females and 30 males, with a mean age of 57 years old, for a total of 118 intracranial aneurysms. Sixty-five patients had a recent history of ruptured aneurysm, 10 suffered from a previous subarachnoid hemorrhage and 25 patients had never bled. In the choice of treatment for subarachnoid aneurysm, in accordance with our neurosurgeons, we have not applied a protocol, rather we have followed guidelines in relation to: age, neurological clinical conditions, systemic disease and location of aneurysm. Morphological aspect of immediate aneurysm occlusion was: 60% more or less complete occlusion, 30% loose packing with 10% failures.The clinical outcome at follow-up (1 month-3 years) was: 72 patients without neurological deficits, 19 patients improved pre-existing neurological deficits, 3 patients worsened for procedural complications; 6 patients died (1 patient unrelated).