Development, degeneration and neural network of the bodily self

The question addressed by this dissertation is how the human brain builds a coherent representation of the body, and how this representation is used to recognize its own body. Recent approaches by neuroimaging and TMS revealed hints for a distinct brain representation of human body, as compared with other stimulus categories. Neuropsychological studies demonstrated that body-parts and self body-parts recognition are separate processes sub-served by two different, even if possibly overlapping, networks within the brain. Bodily self-recognition is one aspect of our ability to distinguish between self and others and the self/other distinction is a crucial aspect of social behaviour. This is the reason why I have conducted a series of experiment on subjects with everyday difficulties in social and emotional behaviour, such as patients with autism spectrum disorders (ASD) and patients with Parkinson’s disease (PD). More specifically, I studied the implicit self body/face recognition (Chapter 6) and the influence of emotional body postures on bodily self-processing in TD children as well as in ASD children (Chapter 7). I found that the bodily self-recognition is present in TD and in ASD children and that emotional body postures modulate self and others’ body processing. Subsequently, I compared implicit and explicit bodily self-recognition in a neuro-degenerative pathology, such as in PD patients, and I found a selective deficit in implicit but not in explicit self-recognition (Chapter 8). This finding suggests that implicit and explicit bodily self-recognition are separate processes subtended by different mechanisms that can be selectively impaired. If the bodily self is crucial for self/other distinction, the space around the body (personal space) represents the space of interaction and communication with others. When, I studied this space in autism, I found that personal space regulation is impaired in ASD children (Chapter 9)

Short Implants Versus Bone Augmentation and Longer Implants in Atrophic Maxillae. Five Year Post Loading Results of a Randomised Controlled Trial

PURPOSE. To evaluate whether short (5 to 8.5 mm) dental implants could be a suitable alternative to longer (at least 11.5 mm long) implants for supporting dental prostheses placed in atrophic fully edentulous maxillae augmented with autogenous bone. MATERIALS AND METHODS. Twenty-eight patients with fully edentulous atrophic maxillae having 5 to 9 mm of residual crestal bone height at least 5 mm thick, as measured on CT scans, were randomised into two groups, either to receive four to eight short (5 to 8.5 mm) implants (15 patients) or autogenous bone from the iliac crest to allow the place-ment of at least 11.5 mm-long implants (13 patients). Both bone blocks and windows at lifted maxillary sinuses were covered with rigid resorbable barriers. Grafts were left to heal for 4 months before placing implants, which were submerged. After 4 months, pro-visional reinforced acrylic prostheses or bar-retained overdentures were delivered. Pro-visional prostheses were replaced after 4 months by definitive screw-retained metal-re- sin cross-arch restorations. Outcome measures were: Augmentation, prosthesis or implant failures, any complications, peri-implant marginal bone level changes, and pa-tient satisfaction. Patients were followed-up until 5 years after loading. RESULTS. All patients could be rehabilitated with implant-supported prostheses, but four patients dropped-out from the augmentation group and three from the short implant group. One bilateral sinus lift procedure failed due to infection, though short implants could be placed. Four implants failed in four patients from the augmentation group ver-sus three short implants in three patients (Fisher's exact test P = 0.6500; difference in proportions = -0.17; 95% CI -0.51 to 0.21). No prosthesis failed. Significantly more complica-tions occurred in augmented patients: 12 complications occurred in nine augmented pa-tients versus one complication in the short implant group (Fisher's exact test P = 0.0003; difference in proportions = -0.82; 95%o CI -0.97 to -0.41). Periapical radiographs of only four patients were readable, so no bone level could be measured at 5 years after loading. With the exception of three patients from the augmentation group, who were only partially satisfied with function, all remaining patients were fully satisfied with the treatment (P = 0.0957); all would have the treatment again. CONCLUSIONS. This study showed that in patients with fully edentulous atrophic maxillae, short implants can be a preferable alternative to longer implants placed in bone aug-mented with autogenous bone, the treatment being less invasive, cheaper, faster and associated with fewer complications

Computer-aided design and manufacturing technology applied to total nasal reconstruction

The principles of nasal reconstruction include the need to reconstruct three tissue layers, the need to restore entire skin aesthetical units, and, possibly, the replacement with like tissues. Computer-aided design (CAD) and computer-aided manu- facturing (CAM) technologies were applied to two total nasal reconstructions in male patients who underwent rhinectomy for cancer. Three-dimensional (3D) data were obtained from computerized tomography (CT) scan-derived DICOM files (Digital Imaging and Communications in Medicine), this allowed us to design the shape of the reconstructive nose in order to mimic the native nose and to plan dimensions and angles. A custom-made titanium plate was manufactured for the struc- ture and a bi-dimensional template for the forehead flap was printed. The patients underwent a total nasal reconstruction in three layers: local flaps for the lining, custom-made titanium plate for the structure, and expanded forehead flap for the skin. Forehead flap pedicle was divided 3 weeks postoperatively under local anesthesia in an outpatient clinic, as well as further minor refinements. The patients underwent a 6-month post-operative CT scan in order to compare the result to the planned nose. No complications were reported. The superimposition demonstrated a 92% match in case 1 and 95% match in case 2 between the reconstructed nose and the planned one. Forehead flap is still the most favorable option for nasal reconstruction, CAD technology allows to implement the planning and makes the procedure easier; moreover, the use of a CAM plate for the structure allows to reconstruct a nose with the desired naso-frontal angle

Brain correlates of spike and wave discharges in GLUT1 deficiency syndrome

Purpose To provide imaging biomarkers of generalized spike-and-wave discharges (GSWD) in patients with GLUT1 deficiency syndrome (GLUT1DS). Methods Eighteen GLUT1DS patients with pathogenetic mutation in SLC2A1 gene were studied by means of Video-EEG simultaneously recorded with functional MRI (VideoEEG-fMRI). A control group of sex and age-matched patients affected by Genetic Generalized Epilepsy (GGE) with GSWD were investigated with the same protocol. Within and between groups comparison was performed as appropriated. For GLUT1DS, correlations analyses between the contrast of interest and the main clinical measurements were provided. Results EEG during fMRI revealed interictal GSWD in 10 GLUT1DS patients. Group-level analysis showed BOLD signal increases at the premotor cortex and putamen. With respect to GGE, GLUT1DS patients demonstrated increased neuronal activity in the putamen, precuneus, cingulate cortex, SMA and paracentral lobule. Whole-brain correlation analyses disclosed a linear relationship between the GSWD-related BOLD changes and the levels of glycorrhachia at diagnosis over the sensory-motor cortex and superior parietal lobuli. Conclusion The BOLD dynamics related to GSWD in GLUT1DS are substantially different from typical GGE showing the former an increased activity in the premotor-striatal network and a decrease in the thalamus. The revealed hemodynamic maps might represent imaging biomarkers of GLUT1DS, being potentially useful for a precocious diagnosis of this genetic disorder

Reconstructive Options after Oncological Rhinectomy: State of the Art

Background: The nose is a central component of the face, and it is fundamental to an individual's recognition and attractiveness. The aim of this study is to present a review of the last twenty years literature on reconstructive techniques after oncological rhinectomy. Methods: Literature searches were conducted in the databases PubMed, Scopus, Medline and Google Scholar. "Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA)" for scoping review was followed. Results: Seventeen articles regarding total rhinectomy reconstruction were finally identified in the English literature, with a total of 447 cases. The prostheses were the reconstructive choice in 213 (47.7%) patients, followed by local flaps in 172 (38.5%) and free flaps in 62 (13.8%). The forehead flap (FF) and the radial forearm free flap (RFFF) are the most frequently used flaps. Conclusions: This study shows that both prosthetic and surgical reconstruction are very suitable solutions in terms of surgical and aesthetic outcomes for the patient

fMRI-Based Effective Connectivity in Surgical Remediable Epilepsies: A Pilot Study

Simultaneous EEG-fMRI can contribute to identify the epileptogenic zone (EZ) in focal epilepsies. However, fMRI maps related to Interictal Epileptiform Discharges (IED) commonly show multiple regions of signal change rather than focal ones. Dynamic causal modeling (DCM) can estimate effective connectivity, i.e. the causal effects exerted by one brain region over another, based on fMRI data. Here, we employed DCM on fMRI data in 10 focal epilepsy patients with multiple IED-related regions of BOLD signal change, to test whether this approach can help the localization process of EZ. For each subject, a family of competing deterministic, plausible DCM models were constructed using IED as autonomous input at each node, one at time. The DCM findings were compared to the presurgical evaluation results and classified as: "Concordant" if the node identified by DCM matches the presumed focus, "Discordant" if the node is distant from the presumed focus, or "Inconclusive" (no statistically significant result). Furthermore, patients who subsequently underwent intracranial EEG recordings or surgery were considered as having an independent validation of DCM results. The effective connectivity focus identified using DCM was Concordant in 7 patients, Discordant in two cases and Inconclusive in one. In four of the 6 patients operated, the DCM findings were validated. Notably, the two Discordant and Invalidated results were found in patients with poor surgical outcome. Our findings provide preliminary evidence to support the applicability of DCM on fMRI data to investigate the epileptic networks in focal epilepsy and, particularly, to identify the EZ in complex cases

Mapping the Effect of Interictal Epileptic Activity Density During Wakefulness on Brain Functioning in Focal Childhood Epilepsies With Centrotemporal Spikes

Childhood epilepsy with centrotemporal spikes (CECTS) is the most common type of \u201cself-limited focal epilepsies.\u201d In its typical presentation, CECTS is a condition reflecting non-lesional cortical hyperexcitability of rolandic regions. The benign evolution of this disorder is challenged by the frequent observation of associated neuropsychological deficits and behavioral impairment. The abundance (or frequency) of interictal centrotemporal spikes (CTS) in CECTS is considered a risk factor for deficits in cognition. Herein, we captured the hemodynamic changes triggered by the CTS density measure (i.e., the number of CTS for time bin) obtained in a cohort of CECTS, studied by means of video electroencephalophy/functional MRI during quite wakefulness. We aim to demonstrate a direct influence of the diurnal CTS frequency on epileptogenic and cognitive networks of children with CECTS. A total number of 8,950 CTS (range between 27 and 801) were recorded in 23 CECTS (21 male), with a mean number of 255 CTS/patient and a mean density of CTS/30 s equal to 10,866 \ub1 11.46. Two independent general linear model models were created for each patient based on the effect of interest: \u201cindividual CTS\u201d in model 1 and \u201cCTS density\u201d in model 2. Hemodynamic correlates of CTS density revealed the involvement of a widespread cortical\u2013subcortical network encompassing the sensory-motor cortex, the Broca's area, the premotor cortex, the thalamus, the putamen, and red nucleus, while in the CTS event-related model, changes were limited to blood\u2013oxygen-level-dependent (BOLD) signal increases in the sensory-motor cortices. A linear relationship was observed between the CTS density hemodynamic changes and both disease duration (positive correlation) and age (negative correlation) within the language network and the bilateral insular cortices. Our results strongly support the critical role of the CTS frequency, even during wakefulness, to interfere with the normal functioning of language brain networks

Mapping the Effect of Interictal Epileptic Activity Density During Wakefulness on Brain Functioning in Focal Childhood Epilepsies With Centrotemporal Spikes

Childhood epilepsy with centrotemporal spikes (CECTS) is the most common type of \u201cself-limited focal epilepsies.\u201d In its typical presentation, CECTS is a condition reflecting non-lesional cortical hyperexcitability of rolandic regions. The benign evolution of this disorder is challenged by the frequent observation of associated neuropsychological deficits and behavioral impairment. The abundance (or frequency) of interictal centrotemporal spikes (CTS) in CECTS is considered a risk factor for deficits in cognition. Herein, we captured the hemodynamic changes triggered by the CTS density measure (i.e., the number of CTS for time bin) obtained in a cohort of CECTS, studied by means of video electroencephalophy/functional MRI during quite wakefulness. We aim to demonstrate a direct influence of the diurnal CTS frequency on epileptogenic and cognitive networks of children with CECTS. A total number of 8,950 CTS (range between 27 and 801) were recorded in 23 CECTS (21 male), with a mean number of 255 CTS/patient and a mean density of CTS/30 s equal to 10,866 \ub1 11.46. Two independent general linear model models were created for each patient based on the effect of interest: \u201cindividual CTS\u201d in model 1 and \u201cCTS density\u201d in model 2. Hemodynamic correlates of CTS density revealed the involvement of a widespread cortical\u2013subcortical network encompassing the sensory-motor cortex, the Broca's area, the premotor cortex, the thalamus, the putamen, and red nucleus, while in the CTS event-related model, changes were limited to blood\u2013oxygen-level-dependent (BOLD) signal increases in the sensory-motor cortices. A linear relationship was observed between the CTS density hemodynamic changes and both disease duration (positive correlation) and age (negative correlation) within the language network and the bilateral insular cortices. Our results strongly support the critical role of the CTS frequency, even during wakefulness, to interfere with the normal functioning of language brain networks