Intracranial Dural Arteriovenous Fistulas: The Sinus and Non-Sinus Concept

AbstractIntroduction: Dural arteriovenous fistulas (dAVFs) account for 10–15% of all intracranial arteriovenous lesions. Different classification strategies have been proposed in the course of the years. None of them seems to guide the treatment strategy. Objective: We expose the experience of the vascular group at Niguarda Hospital and we propose a very practical classification method based on the location of the shunt. We divide dAVF in sinus and non-sinus in order to simplify our daily practice, as this classification method is simply based on the involvement of the sinuses. Material and Methods: 477 intracranial dural arteriovenous fistulas have been treated. 376 underwent endovascular treatment and 101 underwent surgical treatment. Cavernous sinus DAVFs and Galen ampulla malformations have been excluded from this series as they represent a different pathology per se. 376 dAVFs treated by endovascular approach: 180 were sinus and 179 were non-sinus. 101 dAVFs treated with surgical approach: 15 were sinus and 86 were non-sinus. Discussion: Of the 477 intracranial dAVF the recorded mortality and severe disability was 3% and morbidity less than 4%. All patients underwent a postoperative DSA with nearly 100% of complete occlusion of the fistula. At a mean follow-up of 5 years in one case there was a non-sinus fistula recurrence, due to the presence of a partial clipping of "piè" of the vein. Conclusions: The sinus and non-sinus concept has guided our institution for years and has led to good clinical results. This paper intends to share this practical classification with the neurosurgical community

A Hydrogenated amorphous silicon detector for Space Weather Applications

The characteristics of a hydrogenated amorphous silicon (a-Si:H) detector are presented here for monitoring in space solar flares and the evolution of large energetic proton events up to hundreds of MeV. The a-Si:H presents an excellent radiation hardness and finds application in harsh radiation environments for medical purposes, for particle beam characterization and in space weather science and applications. The critical flux detection threshold for solar X rays, soft gamma rays, electrons and protons is discussed in detail.Comment: 32 pages, 13 figures, submitted to Experimental Astronom

Pediatric colloid cysts: a multinational, multicenter study. An IFNE-ISPN-ESPN collaboration

OBJECTIVE Colloid cysts (CCs) are rare at all ages, and particularly among children. The current literature on pediatric CC is limited, and often included in mixed adult/pediatric series. The goal of this multinational, multicenter study was to combine forces among centers and investigate the clinical course of pediatric CCs. METHODS A multinational, multicenter retrospective study was performed to attain a large sample size, focusing on CC diagnosis in patients younger than 18 years of age. Collected data included clinical presentation, radiological characteristics, treatment, and outcome. RESULTS One hundred thirty-four children with CCs were included. Patient age at diagnosis ranged from 2.4 to 18 years (mean 12.8 ± 3.4 years, median 13.2 years, interquartile range 10.3–15.4 years; 22% were \u3c 10 years of age). Twenty-two cases (16%) were diagnosed incidentally, including 48% of those younger than 10 years of age. Most of the other patients had symptoms related to increased intracranial pressure and hydrocephalus. The average follow-up duration for the entire group was 49.5 ± 45.8 months. Fifty-nine patients were initially followed, of whom 28 were eventually operated on at a mean of 19 ± 32 months later due to cyst growth, increasing hydrocephalus, and/or new symptoms. There was a clear correlation between larger cysts and symptomatology, acuteness of symptoms, hydrocephalus, and need for surgery. Older age was also associated with the need for surgery. One hundred three children (77%) underwent cyst resection, 60% using a purely endoscopic approach. There was 1 death related to acute hydrocephalus at presentation. Ten percent of operated patients had some form of complication, and 7.7% of operated cases required a shunt at some point during follow-up. Functional outcome was good; however, the need for immediate surgery was associated with educational limitations. Twenty operated cases (20%) experienced a recurrence of their CC at a mean of 38 ± 46 months after the primary surgery. The CC recurrence rate was 24% following endoscopic resection and 15% following open resections (p = 0.28). CONCLUSIONS CCs may present in all pediatric age groups, although most that are symptomatic present after the age of 10 years. Incidentally discovered cysts should be closely followed, as many may grow, leading to hydrocephalus and other new symptoms. Presentation of CC may be acute and may cause life-threatening conditions related to hydrocephalus, necessitating urgent treatment. The outcome of treated children with CCs is favorable

Italian Guidelines in diagnosis and treatment of alopecia areata

Alopecia areata (AA) is an organ-specific autoimmune disorder that targets anagen phase hair follicles. The course is unpredictable and current available treatments have variable efficacy. Nowadays, there is relatively little evidence on treatment of AA from well-designed clinical trials. Moreover, none of the treatments or devices commonly used to treat AA are specifically approved by the Food and Drug Administration. The Italian Study Group for Cutaneous Annexial Disease of the Italian Society of dermatology proposes these Italian guidelines for diagnosis and treatment of Alopecia Areata deeming useful for the daily management of the disease. This article summarizes evidence-based treatment associated with expert-based recommendations

Valutazione della prestazione sismica di partizioni in cartongesso con prove su tavola vibrante

Le partizioni in cartongesso appartengono alla categoria dei componenti non strutturali, il cui comportamento sismico è oggi riconosciuto come un problema rilevante nell'ambito del “Performance-Based Earthquake Engineering”. In questo lavoro si descrivono prove su tavola vibrante effettuate per studiare il comportamento sismico di pareti di cartongesso a diversi livelli di intensità sismica. Al fine di simulare il comportamento di un generico piano in un edificio, è stato idoneamente progettato e realizzato un telaio di prova in acciaio. Le partizioni sono state inserite all'interno del telaio di prova senza fissarle rigidamente alla struttura, permettendo di ottenere quindi significativi spostamenti di interpiano senza indurre eccessive sollecitazioni nelle partizioni. Con lo scopo di riprodurre sulle partizioni gli effetti realistici di un terremoto, sono stati eseguiti test bidirezionali indagando quindi sia il comportamento in piano che fuori dal piano degli stessi. Come input per le prove, sono stati selezionati due accelerogrammi “spettrocompatibili” in accordo a quanto previsto dalla normativa statunitense per i componenti non strutturali “AC156”. Gli accelerogrammi sono stati quindi scalati a diversi livelli di intensità. Le pareti di cartongesso hanno esibito un buon comportamento sismico, sia nel piano che fuori dal piano

Shake Table Tests on Plasterboard Continuous Ceilings

In the last years, the scientific community research effort is moving towards the investigation of the seismic behaviour of nonstructural components. In this paper, full-scale experimental testing are designed and implemented to investigate the seismic behaviour of a typology of nonstructural components: the plasterboard continuous suspended ceilings. A set of five accelerograms are selected matching the target response spectrum, provided by the USA code for nonstructural components seismic qualification (AC 156). These accelerograms, representative of different intensity levels, are then applied to the test setup. Three limit states (occupancy, damage and life safety limit state) are considered in this study to characterize the seismic response of suspended ceiling systems. The ceilings tested show no damage at all intensity level, resulting in a low fragility. An interesting comparison is made with a previous vulnerability study on a ceiling system with discrete plasterboard tiles

Prove su tavola vibrante di controsoffitti continui in cartongesso

Negli ultimi anni è notevolmente cresciuto l’interesse e l’impegno della ricerca scientifica internazionale verso il comportamento sismico dei componenti non strutturali. A tal proposito, in questo articolo sono presentati i risultati di prove sperimentali, eseguite su tavola vibrante, progettate e realizzate per studiare il comportamento sismico di una tipologia di componenti non strutturali molto comune: i controsoffitti continui in cartongesso. Utilizzando come spettro di risposta target quello fornito dalla normativa americana per la qualificazione sismica dei componenti non strutturali (AC 156) è stato selezionato un set di cinque accelerogrammi. Tali accelerogrammi, rappresentativi di diversi livelli di intensità, sono stati quindi utilizzati come input nei test eseguiti. Per caratterizzare la risposta sismica dei sistemi di controsoffitto testati, così come comunemente indicato nelle principali normative tecniche internazionali, si è fatto riferimento a tre stati limite (operatività, danno e salvaguardia della vita). Ai diversi livelli di intensità sismica a cui sono stati sottoposti durante le prove, i controsoffitti non hanno mostrano alcun danno, esibendo quindi un livello di vulnerabilità molto basso