Mapping brain structure and function in professional fencers: A model to study training effects on central nervous system plasticity.

Brain magnetic resonance imaging (MRI) studies have shown different patterns of structural and functional reorganization in high-level athletes compared with controls, but little is known about their relationship with interlimb coordination mechanisms. To this aim, we investigated brain structural and functional differences in high-level fencers compared with nonathlete controls and the MRI substrates of interlimb coordination in elite athletes. Fourteen right-handed male fencers (median age = 22.3 years) and 15 right-handed age- and sex-matched healthy subjects (median age = 22.4 years) underwent structural and functional MRI acquisition during the execution of cyclic bimanual-movements as well as during in-phase and antiphase hand/foot-movements of the dominant-right limbs. No between-group differences were found in gray matter volumes and white matter architecture. Active-fMRI showed that controls versus fencers had higher activations in parietal and temporal areas during bimanual-task; whereas fencers versus controls had higher activations in the basal ganglia. During in-phase task, controls versus fencers showed higher activation of right cerebellum, whereas fencers had higher activity mainly in frontal areas. The functional-connectivity (FC) analysis showed that fencers versus controls had an increased FC between left motor cortex and fronto-temporal areas as well as bilateral thalami during the different tasks. Intensive and prolonged fencing activity is associated with brain functional changes mainly involving frontal regions related to high-level motor control and planning of complex tasks. These modifications are likely to reflect an optimization of brain networks involved in motor activities, including interlimb coordination tasks, occurring after intensive training.

Subdural Fluid Collection and Hydrocephalus After Foramen Magnum Decompression for Chiari Malformation Type I: Management Algorithm of a Rare Complication.

BACKGROUND: Chiari malformation type I is a hindbrain abnormality characterized by descent of the cerebellar tonsils beneath the foramen magnum, frequently associated with symptoms or brainstem compression, impaired cerebrospinal fluid circulation, and syringomyelia. Foramen magnum decompression represents the most common way of treatment. Rarely, subdural fluid collection and hydrocephalus represent postoperative adverse events. The treatment of this complication is still debated, and physicians are sometimes uncertain when to perform diversion surgery and when to perform more conservative management. CASE DESCRIPTION: We report an unusual occurrence of subdural fluid collection and hydrocephalus that developed in a 23-year-old patient after foramen magnum decompression for Chiari malformation type I. Following a management protocol, based on a step-by-step approach, from conservative therapy to diversion surgery, the patient was managed with urgent external ventricular drainage, and then with conservative management and wound revision. CONCLUSIONS: Because of the rarity of this adverse event, previous case reports differ about the form of treatment. In future cases, finding clinical and radiologic features to identify risk factors that are useful in predicting if the patient will benefit from conservative management or will need to undergo diversion surgery is only possible if a uniform form of treatment is used. Therefore, we believe that a management algorithm based on a step-by-step approach will reduce the use of invasive therapies and help to create a standard of care.

Atypical Association of Ethmoidal Encephalocele and Hydrocephalus in an Adult Patient with Autosomal-Dominant Osteopetrosis Type I (ADO-I): A Case Report.

BACKGROUND: Osteopetroses are a heterogeneous group of heritable disorders characterized by increased bone density as the result of defective osteoclast-mediated bone resorption. The autosomal-dominant osteopetrosis type I (ADO-I) is defined by the presence of osteosclerosis involving mainly the skull bones, variably associated with compression of the foramina of cranial nerves and vascular structures, hypertelorism, exophthalmos, and less commonly with hydrocephalus, pseudotumor, and Chiari malformation type I. CASE DESCRIPTION: We describe an adult patient with ADO-I presenting with an atypical association of clinical manifestations that required a tailored management. On admission, the patient complained about chronic headache, recurrent sinusitis, and postnasal drip. Findings of the examination didn't show clear signs of increased intracranial pressure, whereas imaging studies revealed thickening of the skull bones and an unexpected fistula associated with anterior ethmoidal meningoencephalocele. Some days after endoscopic transnasal closure of the fistula, a severe hypertensive hydrocephalus developed, which required a prompt ventriculoperitoneal shunt placement, complicated by a diffuse subarachnoid hemorrhage. The 6-month follow-up showed complete recovery. CONCLUSIONS: After reviewing the literature, we can confirm that ours was the second case of an adult ADO-I patient associated with anterior ethmoidal meningoencephalocele, the first one needing a combined treatment of the encephalocele and hydrocephalus. Because ADO-I is a rare disease with a wide spectrum of clinical manifestations, our case can represent a prototype for the future management of similar cases.

Transcranial direct current stimulation of SMA modulates anticipatory postural adjustments without affecting the primary movement.

Recent works provide evidences that anticipatory postural adjustments (APAs) are programmed with the prime mover recruitment as a shared posturo-focal command. However the ability of the CNS to adjust APAs to changes in the postural context implies that the postural and voluntary components should take different pathways before reaching the representation of single muscles in the primary motor cortex. Here we test if such bifurcation takes place at the level of the supplementary motor area (SMA). TDCS was applied over the SMA in 14 subjects, who produced a brisk index-finger flexion. This activity is preceded by inhibitory APAs, carved in the tonic activity of Biceps Brachii and Anterior Deltoid, and by an excitatory APA in Triceps Brachii. Subjects performed a series of 30 flexions before, during and after 20 min of tDCS in CATHODAL, ANODAL or SHAM configuration. The inhibitory APA in Biceps and the excitatory APA in Triceps were both greater in ANODAL than in SHAM and CATHODAL configurations, while no difference was found among the latter two (ANODAL vs. SHAM: biceps +26.5%, triceps +66%; ANODAL vs. CATHODAL: biceps +20.5%, triceps: +63.4%; for both muscles, ANOVA p<0.02, Tukey p<0.05). Instead, the APA in anterior deltoid was unchanged in all configurations. No changes were observed in prime mover recruitment and index-finger kinematics. Results show that the SMA is involved in modulating APAs amplitude. Moreover, the differential effect of tDCS observed on postural and voluntary commands suggests that these two components of the motor program are already separated before entering SMA.

Preoperative embolization of carotid chemodectoma: a technical challenge that can be customized according to angioarchitecture. Illustrative cases.

Preoperative embolization of carotid paraganglioma is increasingly used to reduce the risk of surgical bleeding obtaining a more precise and extensive tumor resection. Currently the technique can be customized in consideration of the different tumor angioarchitecture, thanks to embolic materials with different vascular penetration: solid particles of polyvinyl-alcohol (PVA), histoacryl glue, and liquid polymer (Onyx(®)). Two cases of swelling dissection with volume progression over time came to our observation. Both patients (45 and 70-year-old women) were studied with neck ultrasound imaging and computed tomography (CT) and/or magnetic resonance (MR). In both cases the radiological investigations confirmed the clinical suspicion of carotid paraganglioma. Both patients were sent for angiography control and preoperative devascularization of the lesion. The treatment was performed under general anesthesia using, depending on the type of tumor vasculature, in case 1 solid particles of PVA and histoacryl glue, and in case 2 Onyx(®) (Covidien, Irvine). The patients successfully underwent excision of the lesion via cervicotomy within a week from the embolization procedure, without any complications. The histological findings confirmed the diagnosis of chemodectoma, and macrophage infiltrates were seen in the regions previously embolized. At one-year follow-up, there was no evidence of recurrent disease. The preoperative embolization of vascular lesions of the neck represents a safe technique that yields the best results when customized over the type of vascularization of the lesion, enabling the use of the most appropriate materials, depending on the case to be treated.