Thesis (M. Med (Rad. Diagn.)) --University of Limpopo, Medunsa Campus, 2011 / Objective: The objective was to determine the incidence of missed pathology on normal non contrast enhanced cranial computed tomography (NECT).Method: Records of cranial computed tomography scans done over a 12 month period at the Dr George Mukhari Hospital were evaluated by three readers. The NECT and contrast enhanced cranial computed tomography (CECT) were read at separate occasions and readers did not have access to a history, each other’s interpretation or to their own interpretation of the NECT when the CECT was evaluated. The data was evaluated and analysed after the 3 readers had seen the cases individually. Interpretation discrepancies were resolved during a meeting between all 3 readers and consensus was reached. Cases with missed pathology on the NECT were evaluated retrospectively at a joint meeting between the 3 readers to determine whether the pathology was visible on the NECT and thus to determine the combined reader error rate. Results: In this study 3.28 % of cases had pathology missed by 3 readers on the NECT. Retrospective viewing reduced this to 1.42% indicating a reader error of 1.85%. This incidence of missed pathology correlates with the most recent studies done. Having a thorough medical history of the patient and selecting those with clinical findings indicating the need for a CECT will reduce the incidence of missed pathology.Conclusion: Patients with a normal NECT and no fever, meningism, confusion, focal/lateralizing signs, a history of tuberculosis or tumours, or risk factors for dural venous sinus thrombosis have a very small chance of missed pathology on NECT. The risk of contrast induced adverse events outweighs the risk of missing pathology on a normal NECT provided there is no clinical indication necessitating a CECT. Omitting unnecessary CECT will in turn reduce the risk of intravenous iodinated contrast and the radiation exposure to the patient. These two factors will ultimately reduce the running cost of the CT department and increase the throughput of patients. Alternatively omitting the NECT will reduce the radiation exposure to the patient.Reporting errors can be reduced by assessing and managing risk factors in each department i.e. viewing conditions and workload.

Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 5 uppsatser.

No description available.

A 10-month-old male SaarloosWolfdog was presented with a history of multiple neurologic deficits that had acutely progressed. Neurologic examination findings localized signs to the cerebrum and brainstem.Magnetic resonance imaging revealed markedly enlarged and gas-filled lateral ventricles with amass effect leading to cerebellar herniation. A right-sided defect of the cribriform plate with a dysplastic ethmoturbinate was identified as the inlet of air and origin of the intraventricular tension pneumocephalus. Surgical findings were consistent with a ruptured, congenital, nasal meningocele.

Objective: While cavernous carotid aneurysms can cause neurological symptoms, their often-uneventful natural course and the increasing options of intravascular aneurysm closure call for educated decision-making. However, evidence-based guidelines are missing. Here, we report 64 patients with cavernous carotid aneurysms, their respective therapeutic strategies, and follow-up. Methods: We included all patients with cavernous carotid aneurysms who presented to our clinic between 2014 and 2020 and recorded comorbidities (elevated blood pressure, diabetes mellitus, and nicotine consumption), PHASES score, aneurysm site, size and shape, therapeutic strategy, neurological deficits, and clinical follow-up. Results: The mean age of the 64 patients (86% female) was 53 years, the mean follow-up time was 3.8 years. A total of 22 patients suffered from cranial nerve deficit. Of these patients, 50% showed a relief of symptoms regardless of the therapy regime. We found no significant correlations between aneurysm size or PHASES score and the occurrence of neurological symptoms. Conclusion: If aneurysm specific symptoms persist over a longer period of time, relief is difficult to achieve despite aneurysm treatment. Patients should be advised by experts in neurovascular centers, weighing the possibility of an uneventful course against the risks of treatment. In this regard, more detailed prospective data is needed to improve individual patient counseling.

A estimulação transcraniana com corrente contínua (ETCC) vem sendo utilizada na reabilitação de diversas patologias que envolvem a disfunção do sistema sensitiva. Apesar disso, a opção para tratamento de parestesias do ramo mandibular nunca foi empregada. Este estudo piloto teve como objetivo avaliar os efeitos da ETCC em pacientes com queixa de parestesia em ramos do nervo mandibular. Seis pacientes com parestesia referida na topografia do ramo alveolar inferior (uni ou bilateral), com sintomas iniciados após cirurgia bucomaxilofacial, receberam 10 sessões de ETCC (2 mA, 20 min). A avaliação sensitiva composta pelo teste de sensibilidade tátil com o estesiômetro Semmes-Weinstein e pelo teste térmico com solução spray -50° C foi realizada previamente ao tratamento e após a quinta e a décima estimulação, em 24 pontos na topografia de inervação do ramo em estudo. Houve melhora significativa na sensibilidade no teste tátil nas regiões hipoestésicas, com a terceira avaliação significativamente diferente da primeira (p-valor= 0,0015), mas não diferente da segunda (p-valor=0,1932). No teste térmico os participantes reconheceram mais pontos gelados com o passar das avaliações (p-valor=0,05). A aplicação de ETCC pareceu melhorar a sensibilidade tátil e térmica, assim como alívio das parestesias decorrentes de cirurgia bucomaxilofacial. / Transcranial direct current stimulation (tDCS) has been used in the rehabilitation of various diseases that involve dysfunction of the sensory system. However, the option for treating the mandibular branch paresthesia has not been already employed. This pilot study aimed to evaluate the effects of tDCS in patients with paresthesia in branches of the mandibular nerve. Six patients had paresthesia of inferior alveolar nerve (unilateral or bilateral) and symptoms that began after maxillofacial surgery. They received 10 sessions of tDCS (2 mA, 20 min). The sensory evaluation was conducted prior to the treatment, after the fifth and after the tenth application in 24 points in the branch innervation of topography study. The evaluation was composed by tactile sensitivity test with the Semmes-Weinstein esthesiometer and thermal test with spray solution -50 ° C. There was significant improvement in the sensitivity during the tactile test in hypoesthesia regions, with the third evaluation significantly different from the first (p-value = 0.0015), but not different from the second evaluation (p-value = 0.1932). In the thermal test, the participants recognized a larger number of cold areas in the course of ratings (p-value = 0.05). The use of tDCS seemed to improve the tactile and thermal sensitivity of paresthesia, as well as the relief of paresthesias caused by oral and maxillofacial surgery.

A estimulação transcraniana com corrente contínua (ETCC) vem sendo utilizada na reabilitação de diversas patologias que envolvem a disfunção do sistema sensitiva. Apesar disso, a opção para tratamento de parestesias do ramo mandibular nunca foi empregada. Este estudo piloto teve como objetivo avaliar os efeitos da ETCC em pacientes com queixa de parestesia em ramos do nervo mandibular. Seis pacientes com parestesia referida na topografia do ramo alveolar inferior (uni ou bilateral), com sintomas iniciados após cirurgia bucomaxilofacial, receberam 10 sessões de ETCC (2 mA, 20 min). A avaliação sensitiva composta pelo teste de sensibilidade tátil com o estesiômetro Semmes-Weinstein e pelo teste térmico com solução spray -50° C foi realizada previamente ao tratamento e após a quinta e a décima estimulação, em 24 pontos na topografia de inervação do ramo em estudo. Houve melhora significativa na sensibilidade no teste tátil nas regiões hipoestésicas, com a terceira avaliação significativamente diferente da primeira (p-valor= 0,0015), mas não diferente da segunda (p-valor=0,1932). No teste térmico os participantes reconheceram mais pontos gelados com o passar das avaliações (p-valor=0,05). A aplicação de ETCC pareceu melhorar a sensibilidade tátil e térmica, assim como alívio das parestesias decorrentes de cirurgia bucomaxilofacial. / Transcranial direct current stimulation (tDCS) has been used in the rehabilitation of various diseases that involve dysfunction of the sensory system. However, the option for treating the mandibular branch paresthesia has not been already employed. This pilot study aimed to evaluate the effects of tDCS in patients with paresthesia in branches of the mandibular nerve. Six patients had paresthesia of inferior alveolar nerve (unilateral or bilateral) and symptoms that began after maxillofacial surgery. They received 10 sessions of tDCS (2 mA, 20 min). The sensory evaluation was conducted prior to the treatment, after the fifth and after the tenth application in 24 points in the branch innervation of topography study. The evaluation was composed by tactile sensitivity test with the Semmes-Weinstein esthesiometer and thermal test with spray solution -50 ° C. There was significant improvement in the sensitivity during the tactile test in hypoesthesia regions, with the third evaluation significantly different from the first (p-value = 0.0015), but not different from the second evaluation (p-value = 0.1932). In the thermal test, the participants recognized a larger number of cold areas in the course of ratings (p-value = 0.05). The use of tDCS seemed to improve the tactile and thermal sensitivity of paresthesia, as well as the relief of paresthesias caused by oral and maxillofacial surgery.

A estimulação transcraniana com corrente contínua (ETCC) vem sendo utilizada na reabilitação de diversas patologias que envolvem a disfunção do sistema sensitiva. Apesar disso, a opção para tratamento de parestesias do ramo mandibular nunca foi empregada. Este estudo piloto teve como objetivo avaliar os efeitos da ETCC em pacientes com queixa de parestesia em ramos do nervo mandibular. Seis pacientes com parestesia referida na topografia do ramo alveolar inferior (uni ou bilateral), com sintomas iniciados após cirurgia bucomaxilofacial, receberam 10 sessões de ETCC (2 mA, 20 min). A avaliação sensitiva composta pelo teste de sensibilidade tátil com o estesiômetro Semmes-Weinstein e pelo teste térmico com solução spray -50° C foi realizada previamente ao tratamento e após a quinta e a décima estimulação, em 24 pontos na topografia de inervação do ramo em estudo. Houve melhora significativa na sensibilidade no teste tátil nas regiões hipoestésicas, com a terceira avaliação significativamente diferente da primeira (p-valor= 0,0015), mas não diferente da segunda (p-valor=0,1932). No teste térmico os participantes reconheceram mais pontos gelados com o passar das avaliações (p-valor=0,05). A aplicação de ETCC pareceu melhorar a sensibilidade tátil e térmica, assim como alívio das parestesias decorrentes de cirurgia bucomaxilofacial. / Transcranial direct current stimulation (tDCS) has been used in the rehabilitation of various diseases that involve dysfunction of the sensory system. However, the option for treating the mandibular branch paresthesia has not been already employed. This pilot study aimed to evaluate the effects of tDCS in patients with paresthesia in branches of the mandibular nerve. Six patients had paresthesia of inferior alveolar nerve (unilateral or bilateral) and symptoms that began after maxillofacial surgery. They received 10 sessions of tDCS (2 mA, 20 min). The sensory evaluation was conducted prior to the treatment, after the fifth and after the tenth application in 24 points in the branch innervation of topography study. The evaluation was composed by tactile sensitivity test with the Semmes-Weinstein esthesiometer and thermal test with spray solution -50 ° C. There was significant improvement in the sensitivity during the tactile test in hypoesthesia regions, with the third evaluation significantly different from the first (p-value = 0.0015), but not different from the second evaluation (p-value = 0.1932). In the thermal test, the participants recognized a larger number of cold areas in the course of ratings (p-value = 0.05). The use of tDCS seemed to improve the tactile and thermal sensitivity of paresthesia, as well as the relief of paresthesias caused by oral and maxillofacial surgery.

Apparue à la fin des années 1990, la tractographie utilise le signal diffusion de l’imagerie par résonance magnétique (IRM) pour détecter l’orientation préférentielle des molécules d’eau et reconstruire l’architecture des tissus biologiques, notamment celle des fibres blanches intra cérébrales. Cette technique a suscité l’engouement de la communauté scientifique en permettant, pour la première fois, l’étude in vivo non invasive des structures anatomiques, et en particulier celle du cerveau. Néanmoins, la description de la trajectoire des fibres blanches reste imprécise dans les zones de croisement de fibres et pour les faisceaux de petite taille comme les nerfs crâniens. De multiples méthodes sont développées aux différents étapes d’acquisition et de post-traitement afin d’améliorer la résolution spatiale et angulaire et augmenter la précision de la reconstruction des fibres. En pratique clinique, la détection de la trajectoire des nerfs crâniens déplacés au contact des tumeurs de la base du crâne pourrait apporter une aide significative dans la stratégie chirurgicale et améliorer le résultat fonctionnel pour les patients.Après avoir rappelé les notions fondamentales nécessaires à la compréhension de chaque étape de la tractographie, nous en présentons l’ « état de l’art » dans le cas particulier des nerfs crâniens. A partir de 21 études de la littérature scientifique, nous détaillons tous les paramètres d’acquisition et de tracking, les algorithmes de reconstruction, le design des régions d’intérêt et le filtrage. Puis, nous développons notre propre pipeline de tractographie et montrons son impact sur la prise en charge chirurgicale à travers une série de 62 cas de tumeurs variées de la base du crâne et 2 vignettes cliniques illustratives. Enfin, nous proposons une nouvelle approche, la full-tractography, avec une utilisation potentielle en routine clinique, notamment lors du planning pré-chirurgical / Tractography is a recent imaging tool that used the diffusion signal from the magnetic resonance imaging (MRI) to detect the preferential orientation of water molecules within the tissues and particularly along white fibers of the brain. This technique has caught the attention of the scientific community describing non-invasively the in vivo white matter architecture. Nonetheless, its application to fiber crossing areas or to small-scale structures, such as cranial nerves, remains inaccurate. New methods are being developed for both the acquisition and post-processing steps to provide a higher angular and spatial resolution imaging, and improve the reconstruction of fibers. In the clinical setting, the detection of the trajectory of the cranial nerves displaced by skull base tumors could be a relevant asset for the surgical strategy and the functional outcome. After reminding the basics to understand each step involved in tractography, we present the current state-of-the-art for application to cranial nerves. From 21 selected studies, we report all parameters of acquisition and tracking, algorithms of reconstruction, the design of the regions of interest, and filtering. We then develop our tractography pipeline and show its value for the surgical management through a 62 case series of various skull base tumors and two clinical images. Finally, we propose a new full-tractography approach that could be implemented in routine, notably for presurgical planning

Pathogenic variants of the huntingtin (HTT) protein and their aggregation have been investigated in great detail in brains of Huntington's disease patients and HTT-transgenic animals. However, little is known about the physiological brain region- and cell type-specific HTT expression pattern in wild type mice and a potential recruitment of endogenous HTT to other pathogenic protein aggregates such as amyloid plaques in cross seeding events. Employing a monoclonal anti-HTT antibody directed against the HTT mid-region and using brain tissue of three different mouse strains, we detected prominent immunoreactivity in a number of brain areas, particularly in cholinergic cranial nerve nuclei, while ubiquitous neuronal staining appeared faint. The region-specific distribution of endogenous HTT was found to be comparable in wild type rat and hamster brain. In human amyloid precursor protein transgenic Tg2576 mice with amyloid plaque pathology, similar neuronal HTT expression patterns and a distinct association of HTT with Abeta plaques were revealed by immunohistochemical double labelling. Additionally, the localization of HTT in reactive astrocytes was demonstrated for the first time in a transgenic Alzheimer's disease animal model. Both, plaque association of HTT and occurrence in astrocytes appeared to be age-dependent. Astrocytic HTT gene and protein expression was confirmed in primary cultures by RT-qPCR and by immunocytochemistry. We provide the first detailed analysis of physiological HTT expression in rodent brain and, under pathological conditions, demonstrate HTT aggregation in proximity to Abeta plaques and Abeta-induced astrocytic expression of endogenous HTT in Tg2576 mice.