A framework for advancing sustainable magnetic resonance imaging access in Africa.

Magnetic resonance imaging (MRI) technology has profoundly transformed current healthcare systems globally, owing to advances in hardware and software research innovations. Despite these advances, MRI remains largely inaccessible to clinicians, patients, and researchers in low-resource areas, such as Africa. The rapidly growing burden of noncommunicable diseases in Africa underscores the importance of improving access to MRI equipment as well as training and research opportunities on the continent. The Consortium for Advancement of MRI Education and Research in Africa (CAMERA) is a network of African biomedical imaging experts and global partners, implementing novel strategies to advance MRI access and research in Africa. Upon its inception in 2019, CAMERA sets out to identify challenges to MRI usage and provide a framework for addressing MRI needs in the region. To this end, CAMERA conducted a needs assessment survey (NAS) and a series of symposia at international MRI society meetings over a 2-year period. The 68-question NAS was distributed to MRI users in Africa and was completed by 157 clinicians and scientists from across Sub-Saharan Africa (SSA). On average, the number of MRI scanners per million people remained at less than one, of which 39% were obsolete low-field systems but still in use to meet daily clinical needs. The feasibility of coupling stable energy supplies from various sources has contributed to the growing number of higher-field (1.5 T) MRI scanners in the region. However, these systems are underutilized, with only 8% of facilities reporting clinical scans of 15 or more patients per day, per scanner. The most frequently reported MRI scans were neurological and musculoskeletal. The CAMERA NAS combined with the World Health Organization and International Atomic Energy Agency data provides the most up-to-date data on MRI density in Africa and offers a unique insight into Africa's MRI needs. Reported gaps in training, maintenance, and research capacity indicate ongoing challenges in providing sustainable high-value MRI access in SSA. Findings from the NAS and focused discussions at international MRI society meetings provided the basis for the framework presented here for advancing MRI capacity in SSA. While these findings pertain to SSA, the framework provides a model for advancing imaging needs in other low-resource settings.

Development and clinical application of Vertebral Metrics: using a stereo vision system to assess the spine.

The biomechanical changes in the spinal column are considered to be the main responsible for rachialgia. Although radiological techniques use ionizing radiation, they are the most applied tools to assess the biomechanics of the spine. To face this problem, non-invasive techniques must be developed. Vertebral Metrics is an ionizing radiation-free instrument designed to detect the 3D position of each vertebrae in a standing position. Using a stereo vision system combined with low intensity UV light, recognition is achieved with software capable of distinguishing fluorescent marks. The fluorescent marks are the skin projection of the vertex of the spinal processes. This paper presents a major development of Vertebral Metrics and its evaluation. It performs a scan in less than 45 s with a resolution on the order of 1 mm, in each spatial direction, therefore, allowing an accurate analysis of the spine. The instrument was applied to patients without associated pathology. Statistically significant differences between consecutive scans were not found. A positive correlation between the 3D positions of each vertebra and the homologous position of the other vertebrae was observed. Using Vertebral Metrics, innovative results can be obtained. It can be used in areas such as orthopedics, neurosurgery, and rehabilitation. Graphical abstract ᅟ.

[Translation, adaptation and psychometric evaluation of the instrument Activity Record (ACTRE)]. / Tradução, adaptação e avaliação psicométrica do questionário Activity Record (ACTRE).

OBJECTIVE: To perform the cultural adaptation of the instrument Activity Record (ACTRE) and evaluate its psychometric qualities. METHOD: Six steps were followed:1) translation of the original instrument, 2) back-translation, 3) formal equivalence assessment, 4) evaluation by an expert in Portuguese language, 5) final critique by experts in the field and 6 ) applying the questionnaire to 53 pregnant women, aged between 18 and 39 years, at two different moments with an interval time of two hours aimed to evaluate the reliability level of temporal stability (test-retest) using the the Intraclass Correlation. RESULTS: The results of the Intraclass Correlation at the level of test / retest reliability ranged between 0.88 and 1.00. The Cronbach's alpha, calculated for all the questions in the activities most often mentioned, was 0.77, we obtained a further significant correlations between the various issues together in this set of activities. CONCLUSION: The Portuguese version of the ACTRE was easily understood by all pregnant women and revealed a high reliability.

The Visual Word Form Area remains in the dominant hemisphere for language in late-onset left occipital lobe epilepsies: A postsurgery analysis of two cases.

Automatic recognition of words from letter strings is a critical processing step in reading that is lateralized to the left-hemisphere middle fusiform gyrus in the so-called Visual Word Form Area (VWFA). Surgical lesions in this location can lead to irreversible alexia. Very early left hemispheric lesions can lead to transfer of the VWFA to the nondominant hemisphere, but it is currently unknown if this capability is preserved in epilepsies developing after reading acquisition. In this study, we aimed to determine the lateralization of the VWFA in late-onset left inferior occipital lobe epilepsies and also the effect of surgical disconnection from the adjacent secondary visual areas. Two patients with focal epilepsies with onset near the VWFA underwent to surgery for epilepsy, with sparing of this area. Neuropsychology evaluations were performed before and after surgery, as well as quantitative evaluation of the speed of word reading. Comparison of the surgical localization of the lesion, with the BOLD activation associated with the contrast of words-strings, was performed, as well as a study of the associated main white fiber pathways using diffusion-weighted imaging. Neither of the patients developed alexia after surgery (similar word reading speed before and after surgery) despite the fact that the inferior occipital surgical lesions reached the neighborhood (less than 1cm) of the VWFA. Surgeries partly disconnected the VWFA from left secondary visual areas, suggesting that pathways connecting to the posterior visual ventral stream were severely affected but did not induce alexia. The anterior and superior limits of the resection suggest that the critical connection between the VWFA and the Wernicke's Angular Gyrus cortex was not affected, which is supported by the detection of this tract with probabilistic tractography. Left occipital lobe epilepsies developing after reading acquisition did not produce atypical localizations of the VWFA, even with foci in the close neighborhood. Surgery for occipital lobe epilepsy should take this into consideration, as well as the fact that disconnection from the left secondary visual areas may not produce alexia.

[Vertebral metrics: application of a new mechanical instrument to evaluate the spinal column]. / Métrica vertebral: a aplicação de uma nova tecnologia na análise da coluna vertebral.

OBJECTIVE: To present the results of the first application of the new technology - Vertebral Metrics - the analysis of the 3D position of the vertex of each spinous process in pregnant women. MATERIAL AND METHODS: The Vertebral Metrics was applied to women without associated pathology in four stages of pregnancy (12, 20, 32, 37 weeks gestation). We applied univariate linear models. RESULTS: We found that the differences that occur during pregnancy are more significant at the position y (anteroposterior). It was found also that there is a positive correlation between the biomechanical position of the vertex of each of the vertebrae with the homologous position of rest. DISCUSSION/CONCLUSION: Through Vertebral Metrics innovative results could be obtained in analyzing biomechanics of the spine. A device that has different applications can be easily adopted in areas such as orthopedics, neurosurgery, pediatrics and rehabilitation. It should also be noted that this instrument is not exhausted in the sample of this research because it can be further applied to the general population.

Objectivo: Apresentar os resultados da primeira aplicação da nova tecnologia ­ Métrica Vertebral ­ na análise da posição 3D do vértice de cada uma das apófises espinhosas, em mulheres grávidas.Material e Métodos: O Métrica Vertebral foi aplicado a mulheres, sem patologia associada, em quatro momentos da gravidez (12, 20, 32, 37 semanas de gestação). Aplicaram-se modelos lineares univariados.Resultados: Observou-se que as diferenças que ocorrem ao longo da gravidez são mais significativas ao nível da posição y (anteroposterior). Verificou-se, igualmente, que existe uma correlação biomecânica positiva entre a posição do vértice de cada uma das vértebras com a posição homóloga das restantes.Discussão/Conclusão: Através do Métrica Vertebral foi possível obter resultados inovadores na análise biomecânica da colunavertebral. É um dispositivo que tem diferentes aplicações podendo ser facilmente adoptado em áreas como ortopedia, neurocirurgia, pediatria e reabilitação. É de realçar ainda que este instrumento não se esgota na amostra da presente investigação pois pode ser futuramente aplicada à população em geral.

Comparative evaluation of the tridimensional spine position measured with a new instrument (Vertebral Metrics) and an optoelectronic system of stereophotogrammetry.

We designed and built a non-invasive instrument, called Vertebral Metrics, to measure the x, y, and z positions of each spinous process of the spine on a standing position. In the present study, we perform a comparative evaluation of Vertebral Metrics, by comparing the results obtained from this instrument with those from a validated optoelectronic system of stereophotogrammetry, with 10 infrared cameras. The sample was composed of 11 women aged between 14 and 39 years. After marking the various points on the spinal column, from the first cervical vertebra to the first sacral vertebra, they were measured first with the new instrument (Vertebral Metrics) and then by means of the optoelectronics system. Afterwards, the results were subjected to a thorough comparison. The statistical comparison of the results was performed using an ANOVA model with three factors (Instrument, Subject, and Vertebra) for the intervertebral distance.

The outcome of elderly patients with cognitive complaints but normal neuropsychological tests.

Elderly patients may present with prominent cognitive complaints and have performances in neuropsychological tests within the normal range for the age and education, and thus do not fulfill the criteria for mild cognitive impairment (MCI). There is insufficient evidence to support the clinical decision in these cases ("pre-MCI"). Forty-three subjects, 11 controls, 15 "pre-MCI," and 17 MCI, were followed for about three and half years with neuropsychological testing and magnetic resonance imaging including volumetric measurements of the hippocampus and amygdala. Two of the "pre-MCI" subjects suffered cognitive and functional deterioration and were diagnosed with dementia. Although the "pre-MCI" subjects as a group had no significant deterioration in neuropsychological tests, they suffered a decline in the total hippocampal volume (P=0.04) along the follow-up time. In contrast, all control subjects remained stable and had no volumetric decreases. As expected, MCI patients underwent significant deterioration in several neuropsychological tests, often progressed to Alzheimer's disease, and showed decreases both in total hippocampal and amygdalar volumes. Elderly people presenting with cognitive complaints may be in an initial phase of a degenerative disorder and should be followed clinically, even if they have normal neuropsychological tests.

Functional brain mapping of ictal activity in gelastic epilepsy associated with hypothalamic hamartoma: a case report.

Hypothalamic hamartomas (HHs) have been demonstrated as the cause of gelastic epilepsy, both by intracranial electrodes and functional imaging. The neocortex becomes secondarily involved, through poorly characterized propagation pathways. The detailed dynamics of seizure spread have not yet been demonstrated, owing to the limited spatial-temporal resolution of available functional mapping. We studied a patient with epilepsy associated with HH and gelastic epilepsy. Simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) of several seizure events were obtained, with blood oxygen level dependent (BOLD) activation of the hamartoma, and left hemisphere hypothalamus, hippocampus, parietal-occipital area, cingulate gyrus, and dorsal-lateral frontal area. Integration of regional BOLD kinetics and EEG power dynamics strongly suggests propagation of the epileptic activity from the HH through the left fornix to the temporal lobe, and later through the cingulate fasciculus to the left frontal lobe. The EEG/fMRI method has the spatial-temporal resolution to study the dynamics of seizure activity, with detailed demonstration of origin and propagation pathways.

Cognitive function correlates with frontal white matter apparent diffusion coefficients in patients with leukoaraiosis.

BACKGROUND AND AIMS: Diffusion weighted imaging (DWI) displays a high sensitivity to white matter changes, even in areas where no lesions are visible. Correlation with vascular risk factors and cognitive dysfunction seems to be feasible using this technique. We aimed to test relations between age, blood pressure and cognitive function,with lesion load and average Apparent Diffusion Coefficient (ADC) values in lesioned (LWM) and in normal appearing white matter (NAWM), in patients with age related white matter lesions (ARWML). METHODS: Subjects were 29 patients (mean age 72.6 +/- 5.2 years) with different severity of ARWML on MRI and no (or mild) disability assessed by the Instrumental Activities of Daily Living Scale. Imaging lesion load was quantified in bilateral frontal, temporal, parieto-occipital, basal ganglia and infratentorial regions, using a simple visual rating scale; ADC was measured bilaterally in Regions of Interest in parieto-occipital and frontal NAWM, and in frontal periventricular LWM. Neuropsychological examination consisted of Raven Colored Progressive Matrices, Rey's Complex Figure, Digit Canceling. Symbol digit Substitution, Inverse Digit Repetition and Verbal Fluency tests. RESULTS: Visual scales scores and ADC were significantly higher in frontal and parieto-occipital regions. Both were significantly correlated to age and blood pressure, in frontal (visual scale scores and ADC) and parieto-occipital regions (ADC). Attention skills were negatively correlated to ADC in LWM and NAWM in frontal regions and with frontal region visual scale scores. CONCLUSION: Our findings suggest that severity of white matter ischemic changes is correlated with worse cognitive function, as well as advanced age and higher blood pressure.A higher vulnerability of frontal white matter to vascular disease seems to play an important role in executive dysfunction, mainly determined by impairment of attentional skills.DWI results suggest this could be true even for NAWM.

Brain mapping of epileptic activity in a case of idiopathic occipital lobe epilepsy (Panayiotopoulos syndrome).

The Panayiotopoulos type of occipital lobe epilepsy has generated great interest, but the particular brain areas involved in the peculiar seizure manifestations have not been established. We studied a patient with the syndrome, using high-resolution EEG and simultaneous EEG and functional magnetic resonance imaging (fMRI). Resolution of the scalp EEG was improved using a realistic spline Laplacian algorithm, and produced a complex distribution of current sinks and sources over the occipital lobe. The spike-related blood oxygen level dependent (BOLD) effect was multifocal, with clusters in lateral and inferior occipital lobe and lateral and anterior temporal lobe. We also performed regional dipole seeding in BOLD clusters to determine their relative contribution to generation of scalp spikes. The integrated model of the neurophysiologic and vascular data strongly suggests that the epileptic activity originates in the lateral occipital area, spreading to the occipital pole and lateral temporal lobe.

The BOLD effect of interictal spike activity in childhood occipital lobe epilepsy.

PURPOSE: Occipital lobe epilepsy (OLE) presents in childhood with different manifestations, age of onset and EEG features that form distinct syndromes. The ictal clinical symptoms are difficult to correlate with onset in particular areas in the occipital lobes, and the EEG recordings have not been able to overcome this limitation. The mapping of epileptogenic cortical regions in OLE remains therefore an important goal in our understanding of these syndromes. METHODS: In this work, three patients with two types of idiopathic childhood OLE were studied with EEG source analysis and also with mapping of the BOLD effect associated with spikes in simultaneous EEG/fMRI recordings. RESULTS: Two patients with late onset OLE provided EEG source localizations in the lateral parietal cortex and in the medial occipital areas. The BOLD activations were more consistent and restricted to the medial parietal-occipital cortex in both cases. One patient with photosensitive idiopathic OLE presented with dipole sources in the medial parietal cortex, but the BOLD activations were widespread over inferior and bilateral occipital areas and also posterior temporal ones. There was little spatial overlap between the EEG and BOLD results, but the localizations suggested by the latter are more consistent with the ictal clinical manifestations of each type of epileptic syndrome. CONCLUSIONS: Overall, the BOLD effect associated with interictal spikes maps epileptogenic areas to different localizations than the ones suggested by EEG source analysis. These maps are similar in two patients with late onset idiopathic OLE, but different from a case of photosensitive idiopathic OLE.