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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Use of Basal‐Bolus Insulin Therapy at Time of Diagnosis of Type 1 Diabetes Mellitus in Pediatric Patients Provides Improved 1st Year Glycemic Control Compared to Conventional NPH Regimens

Schetzina, Karen E. 01 April 2009 (has links)
No description available.
2

Oxidation status as a predictor of disease activity and response to therapy in pediatric patients with inflammatory bowel disease

Weinbren, Nathan Leo 18 June 2019 (has links)
INTRODUCTION: Physiologic and pathophysiologic inflammation is mediated, at least in part, by the generation and release of reactive oxygen species into the local tissue milieu. The chronic inflammation observed in patients with inflammatory bowel disease (IBD) is thought to begin in the lining of the intestine and may progress to involve the entire bowel wall.In an effort to assess disease activity, clinicians rely on costly and technically invasive procedures such as colonoscopies. As such, there is currently a need for the development of less invasive and more cost-effective methods for use in the diagnosis and interval assessment of children and adults with these chronic intestinal inflammatory disorders. OBJECTIVES: The objective of this study was to first determine if ambient redox status can be reliably measured in the stool of patients with IBD. A second aim of the study was to determine if ambient stool redox status was related to underlying diagnosis, clinical disease activity, or response to therapy in patients with IBD . METHODS: We first our ability to measure redox redox standards using three different commercially available devices. Once demonstrated, we then the process of performing sample analysis under various conditions (room tempererture, refrigerated, frozen, or spun/unspun) to determine the conditions under which we were able to achieve the most stable redox assessments. Finally, we conducted a small pilot cohort study in hospitalized pediatric patients with IBD to assess if stool redox status informed about disease activityWe collected stool samples from seven patients admitted to the inpatient gastrointestinal service at Boston Children’s Hospital during a period extending from November of 2018 to March of 2019. RESULTS: Preliminary studies confirmed our ability to accurately measure relative redox status (RRS) using three different apparatuses. Furthermore, we were able to generate dilution curves using juices known to include oxidants, with linear regression r2 values of 0.99. In our patient population, we confirmed our ability to generate a reliable readings and consistent RRS measurements over. Frozen samples displayed less stable and higher RRS than those either refrigerated or kept at room temperature for up to 8-hours. This suggests that freeze-thaw cycles may impact adversely on the stability of oxidants and antioxidants in our samples. The RRS measurements from stool samples collected from patients who were exhibiting active symptoms of their IBD measured about -400 mV, while samples collected from hospitalized patients without IBD manifest RRS readings of about 100 mV. CONCLUSION: This preliminary study demonstrates our ability to measure RRS in the stool of patients with and without IBD. The stability we observed in samples that were either stored at room temperature or refrigerated demonstrated that these represented optimal storage options. Additionally, measurements from homogenized stool samples appeared to be more variable when compared to the relatively smaller range from centrifuged samples. Initial studies indicated a strong difference in RRS measurements between patients with inflammatory and non-inflammatory GI disease or inactive IBD. This difference suggests that measurements of RRS could provide a quantitative real-time assessments of disease activity and response to therapy in patients with IBD.
3

Avaliação do desenvolvimento pondero-estatural em pacientes pediátricos submetidos a transplante renal no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo / Evaluation of development weight-height on pediatric patients who suffered kidney transplant at the Clinics Hospital of Ribeirão Preto of Medical School of University of Sao Paulo

Lima, Gilson José de 01 June 2015 (has links)
Introdução: A prevalência de doença renal crônica na faixa etária pediátrica ainda é desconhecida. O tratamento de escolha é o transplante renal, independente da idade. Os principais objetivos do tratamento são a manutenção do desenvolvimento físico, neurológico e esquelético, prevenção da doença do metabolismo mineral e ósseo (DMMO), adequada maturação sexual e da função endócrina. O déficit de crescimento está relacionado com a idade de surgimento da insuficiência renal e ocorre devido à má-nutrição energético-calórica, DMMO e uso de corticoide, além dos efeitos deletérios da anemia, uremia e resistência ao hormônio do crescimento. Causas relacionadas ao paciente como retardo de crescimento intra-uterino e malformações congênitas também estão relacionadas. Objetivos: avaliar o desenvolvimento pondero-estatural dos pacientes pediátricos submetidos a transplante renal no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (HC FMRP-USP). Casuística: revisão dos prontuários dos pacientes pediátricos submetidos a transplante renal no HC FMRP-USP e análise do desenvolvimento pondero-estatural comparando os score-z altura para idade e índice de massa corporal (IMC) para idade durante o acompanhamento. As variáveis analisadas foram sexo, faixa etária, uso de Basiliximab, realização ou não de diálise, tipo de transplante realizado (doador falecido ou doador vivo relacionado), hipertensão arterial, dose de manutenção de prednisona. Resultados: foi possível avaliar os dados de 31 pacientes, 10 femininos e 21 masculinos. Ao longo do tempo houve ganho significativo em peso (p< 0,0001) e estatura (p< 0,0001) mas nenhuma das variáveis analisadas mostrou diferença estatisticamente significativa. Houve interação significativa do uso de Basiliximab e da faixa etária sobre o IMC e do uso de Basiliximab, faixa etária e dose de prednisona utilizada sobre a evolução da estatura. A estatura manteve abaixo da média padrão durante todo o acompanhamento e nenhum paciente atingiu a altura final esperada. O IMC estava abaixo da média padrão na ocasião do transplante mas a partir do primeiro ano recuperou e manteve estável em torno do percentil 0. Conclusões: a doença renal crônica na infância compromete o desenvolvimento ponderoestatural dos pacientes afetados. / Introduction: The prevalence of chronic kidney disease in the pediatric age range is still unknown. The treatment of choice is a renal transplant, regardless of age. The main objectives of treatment are the maintenance of physical, neurological and skeletal development, the prevention of renal osteodystrophy, and appropriate sexual and endocrine function maturation. The growth deficit is related to the age at onset of renal failure and is due to energy-calorie malnutrition, to renal osteodystrophy and to corticoid use, in addition to the deleterious effects of anemia, uremia and of resistance to growth hormone. Additional patient-related causes are intrauterine growth retardation and congenital malformations. Objectives: to assess the weight-height development of pediatric patients submitted to renal transplantation at the University Hospital, Faculty of Medicine of Ribeirão Preto, University of São Paulo (HC FMRP-USP). Patients: The medical records of pediatric patients submitted to renal transplantation at HC FMRP-USP were reviewed and weight-height development was analyzed by comparing the zscores for height for age and body mass index (BMI) for age during follow-up. The variables analyzed were: sex, age range, use of Basiliximab, having undergone dialysis or not, type of transplant performed (cadaver donor or related live donor), arterial hypertension, and maintenance dose of prednisone. Results: it was possible to assess the data of 31 patients, 10 girls and 21 boys. A significant weight gain (p<0.0001) and height (p<0.0001) occurred over time but none of the variables analyzed showed a statistically significant difference. There was a significant interaction between age range and BMI, between the use of Basiliximab and age range and between the prednisone dose used and height evolution. Height was below the standard mean value throughout follow-up and no patient reached the expected final height. BMI was below the standard mean value at the time of transplantation, but recovered after the first year and remained stable at a value of about 0. Conclusions: renal failure during childhood compromises the weight-height development of affected patients.
4

Avaliação do desenvolvimento pondero-estatural em pacientes pediátricos submetidos a transplante renal no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo / Evaluation of development weight-height on pediatric patients who suffered kidney transplant at the Clinics Hospital of Ribeirão Preto of Medical School of University of Sao Paulo

Gilson José de Lima 01 June 2015 (has links)
Introdução: A prevalência de doença renal crônica na faixa etária pediátrica ainda é desconhecida. O tratamento de escolha é o transplante renal, independente da idade. Os principais objetivos do tratamento são a manutenção do desenvolvimento físico, neurológico e esquelético, prevenção da doença do metabolismo mineral e ósseo (DMMO), adequada maturação sexual e da função endócrina. O déficit de crescimento está relacionado com a idade de surgimento da insuficiência renal e ocorre devido à má-nutrição energético-calórica, DMMO e uso de corticoide, além dos efeitos deletérios da anemia, uremia e resistência ao hormônio do crescimento. Causas relacionadas ao paciente como retardo de crescimento intra-uterino e malformações congênitas também estão relacionadas. Objetivos: avaliar o desenvolvimento pondero-estatural dos pacientes pediátricos submetidos a transplante renal no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (HC FMRP-USP). Casuística: revisão dos prontuários dos pacientes pediátricos submetidos a transplante renal no HC FMRP-USP e análise do desenvolvimento pondero-estatural comparando os score-z altura para idade e índice de massa corporal (IMC) para idade durante o acompanhamento. As variáveis analisadas foram sexo, faixa etária, uso de Basiliximab, realização ou não de diálise, tipo de transplante realizado (doador falecido ou doador vivo relacionado), hipertensão arterial, dose de manutenção de prednisona. Resultados: foi possível avaliar os dados de 31 pacientes, 10 femininos e 21 masculinos. Ao longo do tempo houve ganho significativo em peso (p< 0,0001) e estatura (p< 0,0001) mas nenhuma das variáveis analisadas mostrou diferença estatisticamente significativa. Houve interação significativa do uso de Basiliximab e da faixa etária sobre o IMC e do uso de Basiliximab, faixa etária e dose de prednisona utilizada sobre a evolução da estatura. A estatura manteve abaixo da média padrão durante todo o acompanhamento e nenhum paciente atingiu a altura final esperada. O IMC estava abaixo da média padrão na ocasião do transplante mas a partir do primeiro ano recuperou e manteve estável em torno do percentil 0. Conclusões: a doença renal crônica na infância compromete o desenvolvimento ponderoestatural dos pacientes afetados. / Introduction: The prevalence of chronic kidney disease in the pediatric age range is still unknown. The treatment of choice is a renal transplant, regardless of age. The main objectives of treatment are the maintenance of physical, neurological and skeletal development, the prevention of renal osteodystrophy, and appropriate sexual and endocrine function maturation. The growth deficit is related to the age at onset of renal failure and is due to energy-calorie malnutrition, to renal osteodystrophy and to corticoid use, in addition to the deleterious effects of anemia, uremia and of resistance to growth hormone. Additional patient-related causes are intrauterine growth retardation and congenital malformations. Objectives: to assess the weight-height development of pediatric patients submitted to renal transplantation at the University Hospital, Faculty of Medicine of Ribeirão Preto, University of São Paulo (HC FMRP-USP). Patients: The medical records of pediatric patients submitted to renal transplantation at HC FMRP-USP were reviewed and weight-height development was analyzed by comparing the zscores for height for age and body mass index (BMI) for age during follow-up. The variables analyzed were: sex, age range, use of Basiliximab, having undergone dialysis or not, type of transplant performed (cadaver donor or related live donor), arterial hypertension, and maintenance dose of prednisone. Results: it was possible to assess the data of 31 patients, 10 girls and 21 boys. A significant weight gain (p<0.0001) and height (p<0.0001) occurred over time but none of the variables analyzed showed a statistically significant difference. There was a significant interaction between age range and BMI, between the use of Basiliximab and age range and between the prednisone dose used and height evolution. Height was below the standard mean value throughout follow-up and no patient reached the expected final height. BMI was below the standard mean value at the time of transplantation, but recovered after the first year and remained stable at a value of about 0. Conclusions: renal failure during childhood compromises the weight-height development of affected patients.
5

Adherence to oral antidiabetic medications in the pediatric population with type 2 diabetes

Adeyemi, Ayoade Olayemi 12 July 2011 (has links)
The present study involved the analyses of the Texas Medicaid prescription claims data. The population studied was made up of subjects between 10 and 18 years who had at least 2 prescriptions of the same oral antidiabetic (OAD) medication from January 1, 2006 through December 31, 2009. Twelve months’ data for each subject were analyzed. The main aim of the study was to describe OAD medication use patterns in the study population, assess trends in Medication Possession Ratio (MPR) and persistence in the study population and determine the relationship between age and MPR and between age and persistence while controlling for covariates. Results of the descriptive statistics, multiple and logistic regression analyses are reported. The average age (± SD) of the 3,109 eligible subjects was 14 (± 2) years; minority populations made up the majority (87%) of the population; 67% of the population were females; and 91% were on the OAD metformin. The overall mean MPR (± SD) for the population was 45% (± 27). A significant negative relationship between MPR and age was reported while controlling for covariates (p<0.0001). Among the covariates, white race and male were significantly associated with a higher MPR, holding other variables constant. When adherence was dichotomized (MPR < 80% and MPR >= 80%), logistic regression analysis also found that age was significantly and negatively related to MPR (p < 0.0001). In addition, the white race and male were again significantly related to a higher level of adherence, holding other variables constant. The overall mean days to non-persistence (± SD) was 108 days (± 86). Persistence was significantly and negatively associated with age, holding other variables constant (p < 0.0001). Among the covariates, white race was significantly related to longer persistence. In conclusion, adherence and persistence are generally low in the study population. Age, gender and race were significantly associated with adherence. Being younger, male, and white were significantly associated with a higher level of adherence, while being younger and white were significantly associated with longer persistence. Healthcare providers therefore need to intensify efforts to improve adherence in pediatric patients especially those at the brink of adulthood. / text
6

Adaptação de um instrumento para classificação de pacientes baseado nas necessidades individualizadas no cuidado de enfermagem do paciente pediátrico oncológico /

Andrade, Sandra de. January 2009 (has links)
Resumo: Este estudo teve como objetivos: (a)avaliar a confiabilidade interavaliadores do instrumento para a classificação de pacientes pediátricos proposto por Dini em uma população de pacientes infanto-juvenil portadores de câncer; (b) Verificar se o instrumento de classificação de pacientes pediátricos proposto por Dini é adequado para pacientes infanto juvenis portadores de câncer. (c) elaborar uma proposta de modificações no instrumento de classificação, permitindo a adaptação para pacientes pediátricos oncológicos. Foram avaliados 34 pacientes na unidade de internação pediátrica de um hospital de câncer, pelas equipes de médicos, enfermeiros e técnicos de enfermagem. Para a avaliação do grau de concordância entre os escores obtidos pelos avaliadores, foi utilizado o coeficiente Kappa. A análise de concordância revelou um Kappa intermediário á alto (K= 069 á 0,84) entre as classificações objetivas, e um Kappa baixo (0,12 á 0,31) nas subjetivas. Conclui-se que o instrumento é confiável e reprodutível, porém para classificação do paciente pediátrico oncológico sugere-se a incorporação de itens complementares para atingir um resultado mais compatível com a realidade desta população. / Abstract: This study aimed to a-) evaluate the reliability of Dini's instrument model for classification pediatric patients in children youth cancer patients; b-) verifying if the classification pediatric patients; c-) preparing a proposal to amend the instrument of classification to pediatric cancer patients. 34 pediatric inpatients from the Cancer Hospital were evaluated by the physicians, nurses and auxiliary nursing team. Kappa's quotient was used to observe the concordance degree of the total scores from the evaluating team. The reliability analysis showed a Kappa from intermediate to high (K= 0,69 to 0,84) for the objective classification and a low Kappa (0,12 to 0,31) which is worthful, however for the reality of this population, it suggests to add complementary itens to reach a better result. / Orientador: Sergio Vicente Serrano / Coorientador: Maria Salete de A. Nascimento / Banca: Sônia Marta Moriguchi / Banca: Juliana França da Mata / Mestre
7

Adaptação de um instrumento para classificação de pacientes baseado nas necessidades individualizadas no cuidado de enfermagem do paciente pediátrico oncológico

Andrade, Sandra de [UNESP] 02 March 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-02Bitstream added on 2014-06-13T19:09:00Z : No. of bitstreams: 1 andrade_s_me_botfm.pdf: 187261 bytes, checksum: f9de178293f9656fe5bb8289177c54fd (MD5) / Fundação Pio Xii - Barretos / Este estudo teve como objetivos: (a)avaliar a confiabilidade interavaliadores do instrumento para a classificação de pacientes pediátricos proposto por Dini em uma população de pacientes infanto-juvenil portadores de câncer; (b) Verificar se o instrumento de classificação de pacientes pediátricos proposto por Dini é adequado para pacientes infanto juvenis portadores de câncer. (c) elaborar uma proposta de modificações no instrumento de classificação, permitindo a adaptação para pacientes pediátricos oncológicos. Foram avaliados 34 pacientes na unidade de internação pediátrica de um hospital de câncer, pelas equipes de médicos, enfermeiros e técnicos de enfermagem. Para a avaliação do grau de concordância entre os escores obtidos pelos avaliadores, foi utilizado o coeficiente Kappa. A análise de concordância revelou um Kappa intermediário á alto (K= 069 á 0,84) entre as classificações objetivas, e um Kappa baixo (0,12 á 0,31) nas subjetivas. Conclui-se que o instrumento é confiável e reprodutível, porém para classificação do paciente pediátrico oncológico sugere-se a incorporação de itens complementares para atingir um resultado mais compatível com a realidade desta população. / This study aimed to a-) evaluate the reliability of Dini’s instrument model for classification pediatric patients in children youth cancer patients; b-) verifying if the classification pediatric patients; c-) preparing a proposal to amend the instrument of classification to pediatric cancer patients. 34 pediatric inpatients from the Cancer Hospital were evaluated by the physicians, nurses and auxiliary nursing team. Kappa’s quotient was used to observe the concordance degree of the total scores from the evaluating team. The reliability analysis showed a Kappa from intermediate to high (K= 0,69 to 0,84) for the objective classification and a low Kappa (0,12 to 0,31) which is worthful, however for the reality of this population, it suggests to add complementary itens to reach a better result.
8

Evaluation of Systemic Steroid Dosing, Asthma-Related Readmissions, and Body Mass Index in Pediatric Patients with Asthma

Tharmarajah, Soba, Phan, Hanna, Haftmann, Richard January 2016 (has links)
Class of 2016 Abstract / Objectives: The purpose of this study was to evaluate whether overweight/obese children with asthma have different systemic steroid dosing practices and asthma related readmission rates compared to normal/underweight children with asthma. Methods: Medical charts of patients admitted between October 2013 and October 2014 for an acute asthma exacerbation were reviewed retrospectively. The primary objective was to compare the average weight based systemic steroid dose between overweight/obese (Group 1) and normal/underweight (Group 2) with asthma. The secondary objective was to compare asthma-related readmissions between both groups. Data collected included demographic data; 30 day, 90 day and 6-month asthma-related readmissions; asthma medications prior-to-admission, during hospitalization and upon discharge. Results: One hundred fifty nine admissions (147 patients with recorded BMI) were evaluated. There was no significant difference in the proportion of obese, overweight, healthy and underweight patients who had 6-month asthma readmissions (p > 0.05). The mean systemic steroid, including prednisone and methylprednisolone, weight based dosing was similar between Group 1 and Group 2 (p > 0.05). Likewise, the proportion of patients with 6-month readmissions was similar in both groups (p > 0.05). Conclusions: Acute asthma exacerbation pediatric patients whom are overweight/obese were not being dosed differently to normal/underweight patients and were not at risk for increased asthma-related readmission in the following 6 months.
9

Sjuksköterskors strategier i bedömningen och omvårdnaden av pediatriska patienter / Nurses´strategies in the assesment and nursing of pediatric patients

Velandia, Fernanda, Stigzelius, Shayarina January 2011 (has links)
Bakgrund: På slutenvårdsavdelningarna vid Astrid Lindgrens barnsjukhus arbetar få specialistutbildade sjuksköterskor vilket kan utgöra en risk för patientsäkerheten. Studier visar att det föreligger behov av fler preventiva åtgärder för att förbättra vårdkvaliteten för de inneliggande pediatriska patienterna. Syfte: Att undersöka sjuksköterskors strategier i bedömningen och omvårdnaden av pediatriska patienter. Metod: En deskriptiv, kvalitativ studie med semistrukturerade intervjuer genomfördes på åtta sjuksköterskor från tre slutenvårdsavdelningar. Kvalitativ manifest innehållsanalys användes. Resultat: Resultatet redovisas i två huvudkategorier: interna strategier och externa strategier. Otillräckliga kunskaper av pediatrisk vård från sjuksköterskornas grundutbildning ledde till att informanterna utförde olika subjektiva interna strategier i bedömning och omvårdnad. När interna strategier inte räckte till använde informanterna externa strategier som innefattade stöd från kollegor, läkare och föräldrar. Samtliga informanter sökte sällan eller aldrig stöd av intensivvårdsavdelningen. Slutsats: Sjuksköterskor utan specialistutbildning har svårigheter att klara av sina åtaganden. Det finns således utrymme för förbättringar i både interna och externa strategier samt ett ökat stöd från intensivvården. / Background: At Astrid Lindgren Children´s Hospital, there is a lack of specialized nurses in the inpatient wards. This could pose a risk to patient safety. Studies show that there is a need for more preventative measures, to improve the quality of care for hospitalized pediatric patients. Objective: To investigate the strategies, used by nurses in the assessment and care of pediatric patients. Method: A descriptive, qualitative study with semistructured interviews. Eight nurses from three inpatient wards were interviewed. Qualitative, manifest content analysis were used. Results: The results are presented in two main categories Internal Strategies and External Strategies. The informants felt that their basic education had given them insufficient knowledge and training in pediatric care. They used subjective, internal strategies when assessing and providing care. External strategies, such as turning to colleagues, doctors and the children´s parents for advice were used when the internal strategies were insufficient. Seeking help and support from the Intensive Care Unit was something the informants rarely or never considered. Conclusion: Non-specialized nurses frequently meet with difficulties in managing their commitments. Our conclusion is that there is room for improvement in internal and external strategies and the need for an increased support from the Intensive Care Unit.
10

Dosimetry-based Assessment of Radiation-associated Cancer risk for \(^9\)\(^9\)\(^m\)Tc-MAG3 Scans in Infants and Optimization of Administered Activities for \(^6\)\(^8\)Ga-labelled Peptides in Children and Adolescents / Dosimetrie-basierte Abschätzung des strahlungsassoziierten Krebsrisikos für \(^9\)\(^9\)\(^m\)Tc-MAG3-Scans bei Säuglingen und Optimierung der verabreichten Aktivitäten für \(^6\)\(^8\)Ga-markierte Peptide bei Kindern und Jugendlichen

Soares Machado, Jéssica January 2019 (has links) (PDF)
In 2006, 0.18 Mio pediatric nuclear medicine diagnostic exams were performed worldwide. However, for most of the radiopharmaceuticals used data on biokinetics and, as a consequence on dosimetry, are missing or have not been made publicly available. Therefore, most of the dosimetry assessments presented today for diagnostic agents in children and adolescents rely on the biokinetics data of adults. Even for one of the most common nuclear medicine exams for this patient group, renal scintigraphy with 99mTc-MAG3 for assessing renal function measured data on biokinetics is available only from a study performed on four children of different ages. In particular, renal scans are among the most frequent exams performed on infants and toddlers. Due to the young age, this patient group can be classified as a risk group with a higher probability of developing stochastic radiation effects compared to adults. As there are only limited data on biokinetics and dosimetry in this patient group, the aim of this study is to reassess the dosimetry and the associated radiation risk for a larger number of infants undergoing 99mTc-MAG3 renal scans based on a retrospective analysis of existing patient data. Data were collected retrospectively from 34 patients younger than 20 months with normal (20 patients) and abnormal renal function (14 patients) undergoing 99mTc-MAG3 scans. The patient-specific organ activity was estimated based on a retrospective calibration which was performed based on a set of two 3D-printed infant kidneys (newborns: 8.6 ml; 1-year-old: 23.4 ml) filled with known activities. Both phantoms were scanned at different positions along the anteroposterior axis inside a water phantom, providing depth- and size-dependent attenuation correction factors for planar imaging. Time-activity curves were determined by drawing kidney, bladder, and whole body regions-of-interest for each patient, and subsequently applying the calibration factor for conversion of counts to activity. Patient-specific time-integrated activity coefficients were obtained by integrating the organ-specific time-activity curves. Absorbed and effective dose coefficients for each patient were assessed with OLINDA/EXM for the provided newborn and 1-year-old phantom. Based on absorbed dose values, the radiation risk estimation was performed individually for each of the 34 patients with the National Cancer Institute’s Radiation Risk Assessment Tool. The patients’ organ-specific mean absorbed dose coefficients for the patients with normal renal function were 0.04±0.03 mGy/MBq for the kidneys and 0.27±0.24 mGy/MBq for the bladder. This resulted in a mean effective dose coefficient of 0.02±0.02 mSv/MBq. Based on the dosimetry results, the evaluation of the excess lifetime risk (ELR) for the development of radiation-induced cancer showed that the group of newborns has an ELR of 16.8 per 100,000 persons, which is higher in comparison with the 1-year-old group with an ELR of 14.7 per 100,000 persons. With regard to the 14 patients with abnormal renal function, the mean values for the organ absorbed dose coefficients for the patients were: 0.40±0.34 mGy/MBq for the kidneys and 0.46±0.37 mGy/MBq for the bladder. The corresponding effective dose coefficients (mSv/MBq) was: 0.05±0.02 mSv/MBq. The mean ELR (per 100,000 persons) for developing cancer from radiation exposure for patients with abnormal renal function was 29.2±18.7 per 100,000 persons. As a result, the radiation-associated stochastic risk increases with the organ doses, taking age- and gender-specific influences into account. Overall, the lifetime radiation risk associated with the 99mTc-MAG3 scans is very low in comparison to the general population risk for developing cancer. Furthermore, due to the increasing demand for PET-scans in children and adolescents with 68Ga-labelled peptides, in this work published data sets for those compounds were analyzed to derive recommendations for the administered activities in children and adolescents. The recommendation for the activities to be administered were based on the weight-independent effective dose model, proposed by the EANM Pediatric Dosage Card for application in pediatric nuclear medicine. The aim was to derive recommendations on administered activities for obtaining age-independent effective doses. Consequently, the corresponding weight-dependent effective dose coefficients were rescaled according to the formalism of the EANM dosage card, to determine the radiopharmaceutical class of 68Ga-labeled peptides (“multiples”), and to calculate the baseline activities based on the biokinetics of these compounds and an upper limit of the administered activity of 185 MBq for an adult. Analogous to 18F-fluoride, a minimum activity of 14 MBq is recommended. As a result, for those pediatric nuclear medicine applications involving 68Ga-labeled peptides, new values for the EANM dosage card were proposed and implemented based on the results derived in this work. Overall, despite the low additional radiation-related cancer risk, all efforts should be undertaken to optimize administered activities in children and adolescents for obtaining sufficient diagnostic information with minimal associated radiation risk. / Im Jahr 2006 wurden weltweit 0,18 Mio. nuklearmedizinische Diagnostikuntersuchungen bei Kindern durchgeführt. Für die meisten Radiopharmazeutika fehlen jedoch Daten zur Biokinetik und damit zur Dosimetrie oder diese wurden nicht öffentlich zugänglich gemacht. Daher basieren die meisten der heute vorgestellten Dosimetriedaten für Diagnostika bei Kindern und Jugendlichen auf den biokinetischen Daten von Erwachsenen. Selbst für eine der häufigsten nuklearmedizinischen Untersuchungen für diese Patientengruppe, die Nierenszintigraphie mit 99mTc-MAG3 für Bestimmung der Nierenfunktion, wurden Daten zur Biokinetik bisher nur für vier Kinder unterschiedlichen Alters erhoben. Insbesondere Nierenuntersuchungen gehören zu den häufigsten Untersuchungen bei Säuglingen und Kleinkindern. Aufgrund des jungen Alters kann diese Patientengruppe als Hochrisikogruppe mit einer höheren Wahrscheinlichkeit für das Eintreten stochastischer Strahlenwirkungen im Vergleich zu Erwachsenen eingestuft werden. Da es in dieser Patientengruppe nur begrenzte Daten zur Biokinetik und Dosimetrie gibt, ist das Ziel dieser Arbeit, die Dosimetrie und das damit verbundene Strahlenrisiko für eine größere Anzahl von Kleinkindern, die sich 99mTc-MAG3-Nierenscans unterziehen, auf der Grundlage einer retrospektiven Analyse bestehender Patientendaten neu zu bewerten. Die Daten wurden retrospektiv von 34 Patienten unter 20 Monaten mit normaler (20 Patienten) und eingeschränkter Nierenfunktion (14 Patienten) erhoben, bei denen 99mTc-MAG3-Scans durchgeführt wurden. Die patientenspezifische Organaktivität wurde basierend auf einer retrospektiven Kalibrierung abgeschätzt. Diese Kalibrierung basiert auf einem Satz von zwei 3D-gedruckten Säuglingsnieren, die mit bekannten Aktivitäten gefüllt wurden. Beide Phantome wurden an verschiedenen Positionen entlang der anteroposterioren Achse innerhalb eines Wasserphantoms gescannt und lieferten tiefen- und größenabhängige Schwächungskorrekturfaktoren für die planare Bildgebung. Die Zeit-Aktivitäts-Kurven wurden bestimmt, indem für jeden Patienten Nieren-, Blasen- und Ganzkörperregionen eingezeichnet und anschließend der entsprechende Kalibrierfaktor für die Umwandlung der Zählraten in Aktivität angewendet wurde. Patientenspezifische zeitintegrierte Aktivitätskoeffizienten wurden durch Integration der organspezifischen Zeit-Aktivitätskurven ermittelt. Die Energie- und effektiven Dosiskoeffizienten für jeden Patienten wurden mit OLINDA/EXM für das bereitgestellte Neugeborenen- und 1-Jahres-Phantom ermittelt. Basierend auf diesen Werten für die Energiedosen wurde eine individuelle Abschätzung des Strahlenrisikos für jeden der 34 Patienten mit dem Radiation Risk Assessment Tool des National Cancer Institute durchgeführt. Die organspezifischen mittleren Energiedosiskoeffizienten der Patienten mit normaler Nierenfunktion lagen bei 0,04±0,03 mGy/MBq für die Nieren und 0,27±0,24 mGy/MBq für die Blase, was in einem mittleren effektiven Dosiskoeffizienten von 0,02±0,02 mSv/MBq resultiert. Basierend auf den Ergebnissen der Dosimetrie, zeigte die Auswertung des zusätzlichen Lebenszeitrisikos ("excess lifetime risk", ELR) für die Entwicklung von strahleninduziertem Krebs, dass die Gruppe der Neugeborenen ein ELR von 16,8 pro 100.000 Personen aufweist, was höher ist als das der Gruppe der 1-jährigen mit 14,7 pro 100.000 Personen. Bei den 14 Patienten mit abnormaler Nierenfunktion waren die Mittelwerte für die Koeffizienten der organspezifischen Energiedosen für die Patienten: 0,40±0,34 mGy/MBq für die Nieren; 0,46±0,37 mGy/MBq für die Blase. Der effektivendosiskoeffizienten (mSv/MBq) waren: 0,05±0,02 mSv/MBq. Der mittlere ELR (pro 100.000 Personen) für die Entstehung von Krebs durch die Strahlenexposition von Patienten mit abnormaler Nierenfunktion betrug 29,2±18,7 pro 100.000 Personen. Das mit der Strahlung verbundene stochastische Risiko steigt mit den Organdosen unter Berücksichtigung alters- und geschlechtsspezifischer Einflüsse. Im Allgemeinen ist das mit den 99mTc-MAG3-Scans verbundene lebenslange Strahlenrisiko im Vergleich zum allgemeinen Bevölkerungsrisiko für die Entstehung von Krebs sehr gering. Aufgrund der steigenden Nachfrage nach PET-Scans bei Kindern und Jugendlichen mit 68Ga-markierten Peptiden wurden zusätzlich publizierte Datensätze für diese Verbindungen analysiert, um Empfehlungen für zu verabreichende Aktivitäten bei Kindern und Jugendlichen abzuleiten. Die Dosisberechnungen dazu basierten auf dem Modell einer gewichtsunabhängigen effektiven Dosis, das von der EANM Pediatric Dosage Card für den Einsatz in der pädiatrischen Nuklearmedizin vorgeschlagen wurde. Ziel war es, Empfehlungen zu verabreichenden Aktivitäten so aufzuteilen, dass sich altersunabhängige effektive Dosen ergeben. Dazu wurden die entsprechenden gewichtsabhängigen effektiven Dosiskoeffizienten gemäß dem Formalismus der EANM-Dosierungsempfehlung neu berechnet, um die radiopharmazeutische Klasse der 68Ga-markierten Peptide ("Multiples") zu bestimmen und die Werte für Basisaktivität zu berechnen. Diese basierend auf den Biokinetiken dieser Verbindungen und einer Obergrenze der verabreichten Aktivität von 185 MBq für einen Erwachsenen. Analog zu 18F-Fluorid, wird eine Mindestaktivität von 14 MBq empfohlen. Darauf basierend wurden für die pädiatrischen nuklearmedizinischen Anwendungen mit 68Ga-markierten Peptiden neue Werte für die EANM-Dosierungsempfehlung vorgeschlagen. Insgesamt sollten, trotz des geringen zusätzlichen strahlenbedingten Krebsrisikos, alle Anstrengungen unternommen werden, um die verabreichten Aktivitäten bei Kindern und Jugendlichen zu optimieren, um ausreichende diagnostische Informationen bei minimalem zusätzlichem Strahlenrisiko zu erhalten.

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