Spin injection in the doped bad metal SrTiO3

In this paper, we demonstrate the capability to establish spin-polarized currents in doped SrTiO3 (STO). The results are based on the study of charge and spin transport in STO layers doped by the reversible electromigration of oxygen atoms in resistive-switching La0.7Sr0.3MnO3/STO/Co vertical stacks. The formation of oxygen vacancies inside STO results in a metallic conductivity at temperatures <200–250 K, above which a transitionto an insulating like behavior is detected. A detailed theoretical analysis shows that the behavior of the metallic phase in our samples corresponds to the well-known state of the thermodynamically doped STO featuring the so-called bad metal behavior. Thus, our findings introduce this class of unconventional materials as valuable candidates for innovative spintronic devices

Cervical demyelinating lesion presenting with choreoathetoid movements and dystonia

Pseudoathetosis and dystonia are rare manifestations of spinal cord disease that have been already reported in lesions involving the posterior columns at the cervical level. We report two patients with a cervical demyelinating lesion at C3\u2013C4 level presenting with hand dystonia and pseudoathetoid movements. The movement disorder disappeared after steroid treatment. The cases we described highlight the importance of identifying secondary causes of movement disorders that can be reversible with appropriate therapy

Management of growing vestibular schwannomas.

Conservative management of small vestibular schwannomas is frequently proposed as most tumours do not grow. Anyway, tumour growth is reported in 30-40 % of the cases, so that surgery is consequently generally proposed. We primarily observed 161 patients affected by unilateral vestibular schwannomas. All patients were examined by means of gadolinium-enhanced magnetic resonance imaging scans. Tumour growth was recorded in 58 cases (35.8 %) and these subjects set up the group of study. Twenty-two (37.9 %) patients were surgically treated; tumour was always completely removed, all patients had normal facial function after surgery and only one patient suffered from a major complication (cerebellar haematoma). Fourteen patients (24.1 %) were submitted to radiotherapy, while one patient was lost at follow-up and another one died because of other medical reasons. Finally, 20 (34.5 %) subjects continued to be observed for different reasons. The mean follow-up period after identification of growth was 6.1 years. Nine tumours continued to grow, nine tumours stopped growing, one tumour grew and then regressed in size and one tumour decreased. Sixty percent of patients with useful hearing at diagnosis preserved it during the entire observation period. In conclusion, most of VS do not grow; in case of tumour growth, a surgical procedure may be suggested and the outcomes are not negatively influenced by the delay of the procedure. But in some cases, patients can still follow the "wait and scan" policy. In fact, only less than half of the growing tumours continued to grow. Moreover, most of the patients continued to retain a useful hearin

Revascularized giant aneurysm of the anterior communicating artery after surgery and embolization, occluded by placement of a Leo+Baby intracranial stent. A case report.

Balt (Montmorency, France) recently manufactured the Leo+Baby dedicated intracranial stent for arteries with a calibre between 1.5 and 3.10 mm. We describe a patient with a partially thrombosed giant sacciform aneurysm of the anterior communicating artery treated without success by surgery and coil embolization subsequently occluded by placement of a Leo+Baby stent (Balt, Montmorency, France). A 56-year-old man presented with a giant aneurysm in the anterior communicating artery region. Following successive surgical intervention and embolization procedures the patient was referred to us with a revascularized aneurysm measuring 15×9×8 cm. To stabilize the endovascular occlusion a combined treatment was scheduled with coil embolization and stent deployment after dual antiplatelet therapy started five days before the interventional procedure. Treatment was undertaken two weeks later under general anaesthesia and total heparinization. A microcatheter was inserted into the aneurysmal sac and four metal coils were released for a total of 61cm obtaining almost complete occlusion of the aneurysm from the circulation. A Leo+Baby stent (2.5×18 mm) was subsequently deployed across the aneurysm neck. At follow-up angiography two months later the aneurysm appeared substantially excluded from the arterial circulation except for a small portion in the neck. Six months later, four months after suspending antiplatelet therapy, follow-up angiography disclosed the complete exclusion of the aneurysm from the circulation. Deployment of the new ministent through the same microcatheter used to release the coils made the interventional procedure simpler and faster

Disease progression or pseudoprogression after concomitant radiochemotherapy treatment: Pitfalls in neurooncology

Although radionecrosis has been exhaustively described in depth in the neurooncological literature, its diagnosis is still a challenging issue because its radiological pattern is frequently indistinguishable from that of tumor recurrence. This review discusses the causes of radionecrosis and the potential effect of adjuvant chemotherapy concomitant with radiotherapy on its rate and onset. The potential pitfalls in clinical studies attempting to make a differential diagnosis between radionecrosis and disease progression are also discussed

Posterior petrous meningiomas: surgical classification and postoperative outcomes in a case series of 130 patients operated via the retrosigmoid approach

Objective: There is a lack of standardized definition and classification of primary posterior petrous meningiomas (PPM), with consequent challenges in comparing different case series. The aim of our study is to provide an anatomical description and classification of PPM analysing a homogenous series of patients operated via retrosigmoid approach (RSA). Methods: PPM originate laterally to the petro-occipital fissure within the 'venous ring' composed of superior petrosal, sigmoid, inferior petrosal and cavernous sinuses. We proposed a classification based on tumour site of origin, direction of growth relative to the internal acoustic meatus and cranial nerves' displacement. Four types of PPM were defined: retro-meatal (type A), meatal (type B), pre-meatal (type C) and broad-based (type D). One hundred and thirty consecutive patients with PPM who underwent RSA as first-line treatment were retrospectively analysed. Results: The PPM classification predicted clinical presentation, postoperative morbidity and resection rates. Headache, hydrocephalous and cerebellar deficits were more common in type A (59.0%-37.7%-49.2%) and D PPM (66.7%-66.7%-33.3%), hypo/anacusia (87.5%) in type B and trigeminal hypo/anaesthesia (85.0%) in type C PPM. After surgery, patients with type A and D PPM had higher risks to develop cerebellar deficits (11.5%-22.2%), whereas patients with type B and C PPM presented hypo/anacusia (12.5%) and trigeminal deficits (10.0%), respectively. The near-total resection rate was higher in type A (91.8%), followed by types B (82.5%), C (80.0%) and D (77.8%) PPM. Conclusions: The PPM surgical classification has an operative and prognostic relevance. In expert hands, the RSA represents a safe and effective approach to remove PPM