The purpose of this investigation is to determine the pressure-flow relationships in the isolated canine cerebral vascular bed. These relationships in vessels which supply an organ surrounded by bone are theoretically influenced by limiting factors which are not present in those vessels surrounded by soft tissue. An evaluation of the extent of these limitations is essential to thorough understanding of the dynamics of the cerebral vascular bed.

La Enfermedad Vascular Cerebral (EVC) isquémica es una de las entidades más frecuentes a la que se enfrenta en la práctica diaria tanto el neurólogo como el médico general. En el Perú, esta entidad se va constituyendo cada vez más en una de las principales causas de morbi-mortalidad en la población. Según los reportes del año 2001, de la Oficina General de Epidemiología del Ministerio de Salud, en el Perú la EVC representa la cuarta causa de mortalidad general y en la provincia del Callao la tercera causa. (1,2) El impacto de esta entidad trasciende al paciente, llegando a constituir un problema familiar, social, laboral y económico. Las terapias trombolíticas que se usan en la etapa aguda del EVC, que constituyen una herramienta farmacológica poderosa contra esta entidad y que están ampliamente difundidas en los países desarrollados desde hace casi una década; lamentablemente aún no están disponibles para la gran mayoría de la población en un país como el nuestro, debido fundamentalmente al factor económico. Por eso, en nuestra realidad, no nos queda sino otra cosa que prevenir la enfermedad, dado que poco o casi nada podemos hacer para revertirla cuando la observamos en su fase aguda. Para dicha prevención es necesario conocer los factores de riesgos para una EVC isquémica, fundamentalmente los modificables, pues son sobre los cuales podemos actuar a tiempo.

La realización de una tomografía espiral multicorte urgente y la detección de signos precoces de isquemia: como la arteria cerebral media hiperdensa, permiten mejorar el diagnóstico, ajustar el tratamiento, evitar errores terapéuticos graves, informar sobre el pronóstico vital de los pacientes e influye significativamente en la elección del destino de estos. Por ello se busca obtener una cuantificación absoluta y relativa de la densidad en el signo de la arteria cerebral media (ACM) con la finalidad de lograr un valor objetivo para el diagnóstico temprano de isquemia cerebral aguda mediante una tomografía multicorte. Para esto se incluyeron 80 pacientes, 40 con diagnóstico presuntivo de accidente cerebrovascular (ACV) isquémico agudo (edad media 76.9 años) y 40 pacientes controles (edad media 70.1 años), atendidos en el Hospital Nacional Hipólito Unanue y que se realizaron una tomografía cerebral sin contraste con un equipo de 16 filas de detectores. Se realiza la cuantificación absoluta midiendo la densidad en unidades Hounsfield (UH) en el segmento de la ACM visualmente de mayor densidad. También se mide la densidad en el mismo segmento de la ACM contralateral para calcular la diferencia entre ambas arterias, cuantificación relativa. En los pacientes casos, la densidad media de la ACM afectada 53,65 UH (IC 95%: 52,16 a 55,13) es mayor que la de la ACM contralateral 39,24 UH (IC 95%: 38,05 a 40,43) y también es mayor en comparación con la ACM en pacientes controles 41,37 UH (IC 95%: 40,83 a 41,91) (p=0,001). En la cuantificación relativa, la diferencia media entre la densidad de la ACM afectada y la de ACM contralateral en los pacientes casos es de 14,40 UH (IC 95%: 13,29 a 15,51), mientras que en los pacientes controles, la diferencia media entre la densidad de la ACM derecha y la ACM izquierda es 3,64 UH (IC 95%: 3,20 a 4,10). Por lo que se concluye que existen diferencias significativas en la cuantificación absoluta y relativa de la densidad de la ACM en pacientes con ACV isquémico agudo, en comparación con sujetos normales.

Memoria para optar al Título Profesional de Médico Veterinario / Diversos estudios experimentales demuestran que modificaciones medioambientales (por ejemplo: nutricionales y lumínicas), pueden producir alteraciones en el desarrollo normal de la corteza cerebral occipital (visual) y sus conexiones. Por otra parte, es posible que en condiciones naturales, las especies animales hayan desarrollado adaptaciones a las distintas condiciones de luminosidad en que realizan su actividad. Recientemente se ha observado en roedores silvestres, con diferentes periodos de actividad y distinta relación filogenética, Abrothrix olivaceus y Phyllotis darwini, variaciones, estadísticamente significativas, en la densidad neuronal cortical occipital. En esta memoria de título se compararon especies con una mayor relación filogenética, para disminuir al mínimo la variable taxonómica. Se estudió la corteza occipital (visual), de roedores silvestres nativos adultos, de las especies Octodon degus (n = 5) y Octodon bridgesi (n = 3), pertenecientes al Orden Rodentia, Suborden Hystricognatha, Familia Octodontidae, con el propósito de evidenciar cambios detectados a través de la medición de la densidad neuronal, mediante la técnica del disector óptico, en cortes de 40 m, incluidos en celoidina y teñidos con Nissl. O. degus, que presenta un período de actividad diurna en el país, evidenció una densidad neuronal menor (34.32  2.51 x 104 neuronas/mm3) que la observada en O. bridgesi (39.55  0.64 x 104 neuronas/mm3), especie de período de actividad nocturna; lo cual fue estadísticamente significativo (t = 3.44, p < 0.05). Las diferencias encontradas se relacionarían con el tipo de condiciones de luminosidad en que se desenvuelven dichas especies, así como también, de otros factores que se relacionarían con este parámetro, como son la relación predador – presa y la alimentación, entre otras. / Proyecto FIV 9102081

Thesis (M.Sc.(Occupational Therapy))--University of the Witwatersrand, Faculty of Health Sciences, 2013. / Hand function deficits are associated with Cerebral Palsy (CP), and lead to diminished participation in activities of daily living (ADL’s), play and school. A longitudinal experiment incorporating a pre-test-post-test design was used with a convenience sample of 28 children with spastic quadriplegic CP randomly assigned to two groups. Both groups received monthly occupational therapy and a home programme over the three month period, the intervention group received an additional neoprene thumb abductor splint. The Quality of Upper Extremity Skills Test (QUEST) was administered at baseline and again at 3 months to assess changes in underlying impairments contributing to hand function. There were no statistically significant differences between final scores in the control and intervention groups, but a clinically significant improvement in score with the splint on for the intervention group was found. Wearing the splint during functional tasks may be beneficial in improving underlying impairments.

Abstract (for Chapter 2) Objective: The aim was to test the hypothesis that the order is a significant phylogenetic grouping in terms of quantifiable gyrification indices. Method: The gyrification index (GI) was measured from serial sections of the brain of twenty five different mammalian species, representing the different orders i.e. primates, carnivores, artiodactyls and rodents. Image J analysis was used to measure the contours of the cerebral cortex and the GI was calculated using three different methods of analysis i.e. complete vs outer; gyral vs sulcal and outer vs inner surface contours. The measurements were then computed against the brain weights of each species within the order. Results: An increasing GI correlates with an increasing brain weight in all the mammalian orders. Each order has its own specific allometric patterns that are significantly different from the other orders examined. The artiodactyls were the mammals with the most gyrencephalic brains, these species being significantly more gyrencephalic than all other mammals when species of similar brain weights are compared. The North American beaver has an atypically lissencephalic brain for its size, differing from the trend for increased gyrencephaly found in the other rodent species examined. Conclusions: Our results show definite trends and patterns specific to each order. So it would seem that the order is a significant phylogenetic grouping in terms of this neural parameter, from which we can predict with a reasonable degree of certainty, the GI of any species of a particular order, if we know the brain weight. Abstract (for Chapter 3) The mammalian order has proven to be a significant phylogenetic grouping in terms of gyrification from which we can predict with a reasonable degree of certainty, the GI of any species of a particular order, if we know the brain weight. We have attempted in the present study to identify potential causes for gyrification at the class level by investigating relationships at the level of the order. It appears that clues to the extent and pattern of gyrification in the different mammalian orders might be related to the bones that constitute the braincase. The external surface areas of the bones of the cranial vault of seventeen different mammalian species were measured using a microscribe digitiser. These values were plotted against brain weight from which we could then calculate residual values, determining if there was more or less external cranial vault area than expected for the size of the brain. These residuals were then plotted against the gyrification indices determined in a previous study for the species examined. Results indicated that for the primates and artiodactyls the skull may potentially be considered as a limiting factor on the expansion of the cerebral cortex; however, the carnivore and rodent orders show conflicting results which suggest that the relative surface area of the skull appears to have no effect on the quantitative extent of gyrencephaly. These inconclusive findings suggest that causes contributing to the quantitative extent of gyrification across mammals may be multifactorial, and more parameters may need to be included in the analysis to arrive at an answer.

Parenting is inherently stressful at times and several studies have shown that being a caregiver of a child who is disabled is even more stressful. A number of studies have tried to identify demographic and psychosocial variables which are predictive of parenting stress levels. It is obvious from these studies that parenting stress is complex as there is no general consensus as to what the factors are which exacerbate or mediate parenting stress in caregivers of children who are disabled. The aim of this study was therefore to assess the parenting stress levels of caregivers of children who are disabled and to try to establish whether the level of the child’s disability influenced parenting stress levels. Further objectives were to ascertain whether various psychosocial and demographic variables were predictive of parenting stress levels. In order to meet these objectives the Parenting Stress Index/Short Form was sent to caregivers of children with cerebral palsy who were attending Frances Voorweg School in Johannesburg. Caregivers also completed a demographic questionnaire. The severity of disability of the children was classified using the Gross Motor Function Classification System. Thirty-five parenting stress questionnaires were returned to the researcher. Means and frequencies were used to summarise the demographic data. T-tests were performed to establish whether there was any significant difference between the parenting stress levels of caregivers of children who were more functionally disabled and those whose children were less disabled. Pearson’s correlations were used to determine whether there was any correlation between demographic variables and parenting stress levels. The parents of the children in the sample showed clinically significant, and in many cases, pathological levels of parenting stress. This stress was however, not in anyway influenced by the severity of their children’s disabilities. The only variable that correlated strongly to the level of parenting stress was found to be the income level of the family (r=0.8). The results of this study confirm that parenting stress is complex and that it is not a simple matter to predict the parenting stress levels of caregivers of disabled children. Therapists should evaluate the needs of each family individually and follow a family centred approach when managing children with cerebral palsy.

Background No data exist about caregivers’ beliefs surrounding a diagnosis of cerebral palsy (CP), its causes and how this influences caregivers’ perceptions of therapy in poorly-resourced South African settings. Neither is there any information about how rehabilitation therapy influences the life of the child or the caregiver. The appropriateness, the outcomes and the effectiveness of therapy for children with CP in a South African setting have not been studied. Numerous tools and scales for measuring outcomes of rehabilitation relating to both the child and the caregiver are available internationally but none have been validated for use in South Africa. Caregiver-related outcomes were the focus of this study and included maternal well-being and mental health, personal quality of life, availability of support and interaction with the child. These are factors known to potentially be influenced through contact with rehabilitation services. Aims The aims of this study were firstly to ascertain whether caregiver-related outcome measures developed in high-income settings were appropriate for a poorly-resourced South African setting; and secondly, to describe parental perceptions and experiences of rehabilitation therapy received in public service hospitals in disadvantaged areas. Methodology The study was undertaken in two phases. Phase One was a quantitative cross-sectional, analytical study and addressed the first aim. Five scales were identified from the literature as being suitable for measuring the caregiver-related outcomes of interest in this study: the Caregiver-Child Scale, the Family Support Scale, the Personal Quality of Life Scale, the Mental Health Subscale of the Medical Outcomes Study (MOS) Short-form 20 Health Survey, and the Measure of Processes of Care (MPOC) Scale. The first four scales measure aspects of maternal well-being and interaction with the child whilst the MPOC assesses caregivers’ reported experiences of family-centred behaviours of rehabilitation service providers. These scales were modified and adapted to make them relevant to a South African setting through a process that included focus groups with caregivers and experienced therapists. After the modified scales had been translated into six local languages and then back-translated into English, the translators, researcher and interviewers met to discuss discrepancies between the two versions (the original modified English version and the back-translation) and to reach consensus on the final translation. The scales were further refined during a pilot study where two trained interviewers administered the modified scales to 24 caregivers of children attending public service hospitals for therapy. Items in the scales which were confusing for caregivers or which they found difficult to understand were clarified. In addition, where necessary, concrete examples were given of the type of behaviour or action being asked about in the scale. Following the pilot study, two trained interviewers administered the modified scales to a convenience sample of caregivers attending rehabilitation therapy in public service hospitals in Gauteng and Limpopo. The reliability and validity of each scale was assessed using multi-trait scaling and factor analysis. Phase Two employed qualitative methodology to address the second aim of the study. A purposive sample of 24 information-rich caregivers attending therapy in public service hospitals in Gauteng and Limpopo participated in one of five focus groups. The discussions were conducted in local languages. Taped recordings were transcribed and translated into English before being analysed using a grounded theory approach. Results Two hundred and sixty three caregivers from 31 hospitals in Gauteng and Limpopo provinces were interviewed during the first phase of the study. The mean age of their children was 3.3 years (± 2.6).Two-thirds of the children (66%) had severe limitations in motor function and few (15%) could communicate verbally. Only one of the five scales, the Mental Health Subscale, proved to be both reliable and valid in South African settings. A second scale - the MPOC - was potentially useful if reduced to an eight item scale (from the original 20 items). The Family Support Scale was reliable but not valid whilst the Caregiver-Child and Personal Quality of Life Scales were neither reliable nor valid. The process of administering the scales combined with the qualitative data helped to explain why the scales did not perform as well as expected in a South African setting. Reasons for these findings included the caregivers’ inexperience in completing these kinds of questionnaires; their difficulty with the concept of grading their responses which meant that Likert-type scales were difficult for them to complete; and thirdly language and cross-cultural applicability. This was because the scales were developed for very different cultural groups. It was not the questions or scale items that were the problem; it was rather finding the language and words that caregivers themselves would use to express the underlying concepts. The study found that caregivers living in disadvantaged South African settings live very differently from their counterparts in well-resourced areas. They lived in poverty; were beset by financial concerns; often abandoned and rejected by their partners; and endured gossip and ignorant attitudes from their neighbours and the community. The burden of daily care-giving was high as most of the children were severely disabled. This was compounded by concern about the child’s health and the future. Despite this, the study found that they were happy, healthy and generally well satisfied with their lives. Support from informal support structures such as relatives and close family members, together with formal support structures, was an important dimension in helping caregivers cope. Qualitative data from the focus groups yielded information regarding caregivers’ beliefs surrounding the perceived cause of the child’s disability. These ranged from traditional and cultural beliefs to medical explanations, and to frank confusion between the two. This was accompanied by misconceptions about therapy and the outcome thereof. Parental perceptions and experiences of rehabilitation were positive although many caregivers initially expected therapy to provide a cure. Respectful and caring attitudes, “hands on” therapy, practical help and assistance with assistive devices and school placements were aspects of service most valued by caregivers. The study helped define the components of an “ideal” therapy service in disadvantaged South African settings. They would include the availability of parent support groups; greater involvement of fathers, close family members and traditional healers in the rehabilitation process as well as the implementation of innovative strategies to ensure clearer communication and understanding between therapists and caregivers operating in a cross-cultural setting. Elements of care not traditionally perceived as part of therapy such as promoting supportive networks and taking on advocacy role for children with disabilities may offer additional advantages. Conclusion The study confirms the view that scales developed in high-income settings are not necessarily immediately applicable to less well-resourced settings and often require extensive modifications to ensure reliability and validity. Whilst the Mental Health Scale is a reliable and valid tool for caregivers attending public service hospitals in South Africa, other scales, such as the MPOC, a popular scale in North American and Europe, require substantial modification for a South African setting. In addition to highlighting the challenges involved in finding suitable outcome measures of therapy intervention for this population, this study has objectively documented the lives and experiences of caregivers of children with CP in South Africa for the first time together with their experiences and perceptions of rehabilitation therapy. Using this information, the components of an “ideal” rehabilitation service in a disadvantaged South African setting have been identified and described. This may facilitate the establishment of a more effective and appropriate therapy service for caregivers and children with CP living in poor areas.

Para desenvolver e avaliar a aplicabilidade de uma escala técnica prognostica das dificuldades no tratamento microcirúrgico dos aneurismas gigantes e complexos da circulação anterior do polígono de Willis, 50 lesões foram operadas. Um valor numérico foi dado a cada uma das 8 variáveis da escala. Somando-se os valores para cada variável, uma nota (de 1 a 14) foi obtida, para cada uma das 50 cirurgias. Dois grupos, portanto, foram definidos: cirurgia difícil (nota de 1 a 8) e cirurgia extremamente difícil (nota de 9 a 14). Foi feita análise estatística comparando-se os 2 grupos em relação a diversas variáveis demográficas e clínicas. Concluiu-se que a escala proposta é útil no planejamento pré-operatório, intra-operatório e prognóstico neste tipo de aneurisma / In order to develop and verify the applicability of a technical and prognostic scale of the difficulties in the microsurgical treatment of giant and complex aneurysms of the anterior circulation of the Cicle of Willis, 50 lesions were operated. A numeric amount was given for each of 8 variants of the scale. By adding each amount for each variant a score(from 1 to 14) was achieved, for each of the 50 surgeries. Two groups, therefore, were established: difficult surgery (scores from 1 to 8) and extremely difficult surgery (scores from 9 to 14). Statistical assessment comparing both groups in relation to several demographic and clinical variants was done. It was concluded that the proposed scale is useful in preoperative, intraoperative and prognostic planning in microsurgery for this kind of aneurysms

Thesis advisor: Judith A. Vessey / Purpose: The purpose of this study was to elucidate changes in parents' perceptions of health related quality of life (HRQOL), functional status, and caregiver burden in children with severe cerebral palsy (CP) following extensive orthopedic surgery and to determine the amount of nonmedical out-of-pocket expenses (NOOPEs) incurred during hospitalization. Background: CP is the most common cause of childhood physical disability. Children with severe non-ambulatory CP have multiple complex medical problems and frequently develop hip dislocations and neuromuscular scoliosis; these require extensive orthopaedic surgical interventions to prevent progression. The surgical trajectory is costly, resource intensive, and complications are common. Decision-making needs to extend beyond anticipated physical and radiographic improvements to include patient-centered outcomes including HRQOL, functional status, caregiver impact, and financial burden. Currently, research on this second group of outcomes does not exist. Methods: A single group prospective cohort study (N=48) design was used to measure changes pre- and post- surgery. NOOPEs were collected on a daily basis from parents during their child's hospitalization. A linear mixed-model regression analysis for longitudinal data, incorporating serial patient measurements over one year, was used to assess changes in HRQOL, functional status, and caregiver impact using measures normed for this population (i.e., CPCHILD, ACEND). NOOPEs were calculated using descriptive statistics. Results: Significant declines in HRQOL and functional status were noted at six weeks post-operative with return to baseline at three months. Long-term significant (p = .005) improvements, however, were noted beginning at six months. Caregiver impact did not change significantly over time. The total NOOPEs for the inpatient ranged from $59.00-$6977.50 (Median = $479.30) with 1971.5 missed hours from work. Conclusion: Children with severe CP who undergo extensive orthopaedic surgery and their families experience improvements across a variety of patient-centered outcomes in the long-term following surgery. Nursing has a critical role in assisting families in decision-making around surgery and providing anticipatory guidance and support. / Thesis (PhD) — Boston College, 2013. / Submitted to: Boston College. Connell School of Nursing. / Discipline: Nursing.