Rat thyroid graft transplantation after cryopreservation with scintigraphic standardization for an experimental study

Abstract Purpose: Budget cuts among other factors undermine the use of state-of-the-art equipment by many research groups. This doesn't mean that their scientific data are not reliable or top-notch. Resort to adaptations is a recurrent need in their reality. The aim of this study was to assess whether scintigraphy with 99mTcO4 is effective in evaluating the functionality of thyroid grafts after cryopreservation in rats. Material and methods: 24 rats were randomly distributed into 3 groups: Control Group (CG), without surgical procedure, Hypothyroidism Group (HTG), submitted to total thyroidectomy, and Transplanted Group (TG), with total thyroidectomy and cryopreservation of the thyroid gland for 7 days followed by grafting of a thyroid lobe. A protocol using a gamma camera imaging was conducted fourteen weeks after transplantation, and the whole body 99mTc, focusing on the topic of heterotopic thyroid uptake was evaluated. Results: The images acquired had good quality with no noise and artifacts that could jeopardize its analysis. On the 14th day, HTG displayed no thyroid uptake, and the TG had a clear uptake of the thyroid graft in the topography of the biceps femoris muscle. Presented data also showed that both equipment spatial resolution and alignment (4.375 mm) did not interfere with the physiological uptake of 99mTc by the thyroid graft. Conclusion: The viability and functionality of cryopreserved thyroid autotransplantation in rats who underwent total thyroidectomy were successfully accessed by the scintigraphy protocol developed. HIGHLIGHTS Adaptations in validated methods are a recurrent trend due to limited budgets which does not diminish their functionality. Scintigraphy with 99mTcO4 is effective in evaluating the functionality of thyroid grafts after cryopreservation in rats. It is possible to adapt human SPECT for other animals for clinical and research purposes.

A cost-effective way to reduce the equivalent eye lens dose fromYttrium-90 radiopharmaceuticals.

PURPOSE: We analyzed the effect of the use of Eye Protective Equipment (EPE) and the best position to use individual dosimeters to estimate the eye lens radiation dose to a medical staff that works with yttrium-90. METHODS: Three Alderson-Head-Phantoms were exposed to 58MBq of 90Y for 24h, in two different experiments: (1) at different dosimeter placements and (2) with and without the use of EPE. The measurements were carried on by thermoluminescent technique. RESULTS: Doses received by dosimeters on both lenses were more closely represented by the ones placed between the eyes than those on the temples, which underestimated the doses by a factor of 3. Also, the transmission factors showed that the EPE was able to reduce the Hp(3) values from about 78% to 92%. CONCLUSIONS: This study demonstrated that the use of EPE can optimize the 90Y eye lens dose. An individual dosimeter should be worn between the eyes for an appropriate estimate of this equivalent dose.

Monitoring bone changes due to calcium, magnesium, and phosphorus loss in rat femurs using Quantitative Ultrasound.

Bone mineral density is an important parameter for the diagnosis of bone diseases, as well as for predicting fractures and treatment monitoring. Thus, the aim of the present study was to evaluate the potential of Quantitative Ultrasound (QUS) to monitor bone changes after calcium, phosphorus, and magnesium loss in rat femurs in vitro during a demineralization process. Four quantitative ultrasound parameters were estimated from bone surface echoes in eight femur diaphysis of rats. The echo signals were acquired during a decalcification process by Ethylenediaminetetraacetic Acid (EDTA). The results were compared to Quantitative Computed Tomography (QCT) and inductively coupled plasma optical emission spectrometry measurements for validation. Integrated Reflection Coefficient (IRC) reflection parameters and Frequency Slope of Reflection Transfer Function (FSRTF) during demineralization tended to decrease, while the backscattering parameter Apparent Integrated Backscatter (AIB) increased and Frequency Slope of Apparent Backscatter (FSAB) showed an oscillatory behavior with no defined trend. Results indicate a clear relation between demineralization and the corresponding decrease in the reflection parameters and increase in the scattering parameters. The trend analysis of the fall curve of the chemical elements showed a better relationship between IRC and QCT. It was possible to monitor bone changes after ions losses, through the QUS. Thus, it is an indication that the proposed protocol has potential to characterize bone tissue in animal models, providing consistent results towards standardization of bone characterization studies by QUS endorsing its use in humans.

Exploring cortical bone density through the ultrasound integrated reflection coefficient / Densidade óssea cortical analisada pelo coeficiente de reflexão ultrassônica

ABSTRACT Objective: This work evaluates the relationship between ultrasonic reflection and bone density from fourteen cylindrical bovine cortical bone samples (3.0-cm thick). Methods: Twenty US reflection signals per sample were acquired along the bone surface (2.0-mm step). The Integrated Reflection Coefficient (IRC) from each signal was compared to Quantitative Computed Tomography (QCT). Results: Seven IRC and QCT curves presented Pearson's Correlation R-values above 0.5. For weak correlation curves, QCT and IRC showed similar trends in several segments. Conclusion: IRC was sensitive to bone density variation. Level of Evidence: Experimental Study, Investigating a Diagnostic Test.

RESUMO Objetivo: Este estudo avalia a relação entre a reflexão ultrassônica e a densidade óssea de 14 amostras cilíndricas de osso cortical bovino (3,0 cm de espessura). Métodos: Foi realizada a aquisição de 20 sinais de reflexão ultrassônica por amostra (passo de 2,0 mm), ao longo da superfície óssea. O Coeficiente de Reflexão Integrado (IRC) de cada sinal foi comparado por Tomografia Computadorizada Quantitativa (QCT). Resultados: Sete curvas de IRC e QCT apresentaram valor de Correlação R de Pearson acima de 0,5. Para curvas de correlação fraca, QCT e IRC apresentaram tendências semelhantes em vários segmentos. Conclusão: O IRC foi sensível à variação da densidade óssea. Nível de evidência: Estudo Experimental, Investigação de Exame Diagnóstico.

Osteíte condensante de clavícula / Condensing osteitis of the clavicle

Relata-se nesse trabalho um caso de osteíte condensante de clavícula em uma mulher de 28 anos, com historia de estresse articular constante e intenso pela pratica esportiva de treinamento de força, sem referência a traumas nessa topografia. Os exames laboratoriais e de imagem não confirmam outros diagnósticos diferenciais.

This paper reports a case of condensing osteitis of the clavicle in a woman of 28 years, with constant articular stress and intense practice of sports, without reference to trauma in this topography. Laboratory and imaging tests do not confirm other differential diagnoses.

Cytopathologic evaluation of patients submitted to radiotherapy for uterine cervix cancer.

Cervical cancer is an important public health problem. Pap smear is the leading strategy of screening programs for cervical cancer worldwide. However, delayed diagnosis leads to more aggressive and less effective treatments. Patients with uterine cervix malignancies who are referred for radiotherapy have advanced-stage disease, which results in high rates of locoregional recurrence. The use of radiotherapy as a treatment for cervical cancer causes morphological changes in neoplastic and non-neoplastic epithelial cells, as well as in stromal cells, which make it difficult to diagnose the residual lesion, resulting in a dilemma in cytopathological routine. Based on the difficulties of cytopathologic evaluation for the follow-up of patients treated with radiotherapy for cervical cancer, our objective was to describe the actinic cytopathic effects. Our paper was based on a structured review including the period from June 2015 to April 2016, aiming at an exploratory-descriptive study. Bibliographic investigations were carried out through selection and analysis of articles, list of authors and keywords, selection of new articles focused on the analysis of bibliographic references to previously selected documents, as well as textbooks of recognized merit. The most incident actinic cytopathological alterations as described in the literature are: cellular gigantism, nuclear and cytoplasmic vacuolization, dyskeratosis, bi- and multinucleated (B/M) cells, macro and multiple nucleoli, anisokaryosis, anisonucleolosis and nuclear pyknosis. To date, a protocol has not been established that can precisely differentiate the morphological characteristics between benign cells with actinic effects from recurrent malignant cells on post-radiotherapy smears.

Cytopathologic evaluation of patients submitted to radiotherapy for uterine cervix cancer / Avaliação citopatológica no seguimento de pacientes submetidas à radioterapia por câncer de colo uterino

Summary Cervical cancer is an important public health problem. Pap smear is the leading strategy of screening programs for cervical cancer worldwide. However, delayed diagnosis leads to more aggressive and less effective treatments. Patients with uterine cervix malignancies who are referred for radiotherapy have advanced-stage disease, which results in high rates of locoregional recurrence. The use of radiotherapy as a treatment for cervical cancer causes morphological changes in neoplastic and non-neoplastic epithelial cells, as well as in stromal cells, which make it difficult to diagnose the residual lesion, resulting in a dilemma in cytopathological routine. Based on the difficulties of cytopathologic evaluation for the follow-up of patients treated with radiotherapy for cervical cancer, our objective was to describe the actinic cytopathic effects. Our paper was based on a structured review including the period from June 2015 to April 2016, aiming at an exploratory-descriptive study. Bibliographic investigations were carried out through selection and analysis of articles, list of authors and keywords, selection of new articles focused on the analysis of bibliographic references to previously selected documents, as well as textbooks of recognized merit. The most incident actinic cytopathological alterations as described in the literature are: cellular gigantism, nuclear and cytoplasmic vacuolization, dyskeratosis, bi- and multinucleated (B/M) cells, macro and multiple nucleoli, anisokaryosis, anisonucleolosis and nuclear pyknosis. To date, a protocol has not been established that can precisely differentiate the morphological characteristics between benign cells with actinic effects from recurrent malignant cells on post-radiotherapy smears.

Resumo O câncer de colo uterino configura-se como um importante problema de saúde pública. O teste citopatológico é a principal estratégia de programas de rastreamento dessa neoplasia maligna em todo o mundo. Entretanto, a demora no diagnóstico ocasiona tratamentos mais agressivos e menos efetivos. Pacientes com neoplasia maligna de colo uterino que são encaminhadas para radioterapia apresentam doença em estádios avançados, e esse fato determina altos índices de recidiva locorregional. A utilização da radioterapia como tratamento do câncer do colo uterino provoca alterações morfológicas não só nas células epiteliais neoplásicas e não neoplásicas como também nas células estromais, o que dificulta o diagnóstico da lesão residual e resulta em um dilema na rotina citopatológica. Com base nas dificuldades da avaliação citopatológica do seguimento das pacientes pós-radioterapia, o objetivo deste trabalho foi descrever os efeitos citopáticos actínicos. O trabalho teve como base uma revisão estruturada no período de junho de 2015 a abril de 2016, visando a um estudo exploratório-descritivo. As investigações bibliográficas foram realizadas por meio de seleção e análise dos artigos, lista de autores e palavras-chave; seleção de novos artigos focada na análise de referências bibliográficas dos documentos previamente selecionados e livros-texto de relevância conceitual. As alterações citopatológicas actínicas mais incidentes descritas na literatura são: gigantismo celular, vacuolização nuclear e citoplasmática, disceratose, bi e multinucleações, macro e múltiplos nucléolos, anisocariose, anisonucleolose e picnose nuclear. Até o momento, não se conseguiu estabelecer um protocolo que possa diferenciar precisamente as características morfológicas entre células benignas com efeitos actínicos das células malignas recidivantes em esfregaços pós-radioterapia.

99mTc-thymine scintigraphy may be a promising method in the diagnosis of breast cancer.

OBJECTIVE: Mammography has been established as the gold standard for the detection of breast cancer, and imaging techniques such as ultrasonography, magnetic resonance imaging, scintigraphy and positron emission tomography may be useful to improve its sensitivity and specificity. The objective of this study with breast scintigraphy was to evaluate the uptake of 99mTc-thymine in mammary lesions. METHODS: A total of 45 patients were included in this study. Thirty-three patients (73%) were subjected to surgery or percutaneous biopsy, providing histopathological data. The other 12 patients who remained under surveillance received clinical examinations and biannual mammography with a normal follow-up of at least three years, the data from which were used for comparison with the scintimammography results. RESULTS: The majority of patients (64.4%) had clinically impalpable lesions with a mammogram diagnosis of microcalcifications, impalpable nodules, or focal asymmetry. Of the studied lesions, 87% were smaller or equal to 20 mm in diameter, and 22% had malignant histopathological findings. Scintigraphy with 99mTc-thymine had a sensitivity of 70%, a specificity of 85.7%, positive and negative predictive values of 58.3% and 90.9%, respectively, and an accuracy of 82.2%. CONCLUSIONS: The results of this study are consistent with those previously reported by other authors. The good specificity and high negative predictive value of this technique and the absence of uptake in the heart indicate that it may be a promising complementary method in clinical practice and that it may contribute to reducing unnecessary benign biopsies.

99mTc-thymine scintigraphy may be a promising method in the diagnosis of breast cancer

OBJECTIVE: Mammography has been established as the gold standard for the detection of breast cancer, and imaging techniques such as ultrasonography, magnetic resonance imaging, scintigraphy and positron emission tomography may be useful to improve its sensitivity and specificity. The objective of this study with breast scintigraphy was to evaluate the uptake of 99mTc-thymine in mammary lesions. METHODS: A total of 45 patients were included in this study. Thirty-three patients (73%) were subjected to surgery or percutaneous biopsy, providing histopathological data. The other 12 patients who remained under surveillance received clinical examinations and biannual mammography with a normal follow-up of at least three years, the data from which were used for comparison with the scintimammography results. RESULTS: The majority of patients (64.4%) had clinically impalpable lesions with a mammogram diagnosis of microcalcifications, impalpable nodules, or focal asymmetry. Of the studied lesions, 87% were smaller or equal to 20 mm in diameter, and 22% had malignant histopathological findings. Scintigraphy with 99mTc-thymine had a sensitivity of 70%, a specificity of 85.7%, positive and negative predictive values of 58.3% and 90.9%, respectively, and an accuracy of 82.2%. CONCLUSIONS: The results of this study are consistent with those previously reported by other authors. The good specificity and high negative predictive value of this technique and the absence of uptake in the heart indicate that it may be a promising complementary method in clinical practice and that it may contribute to reducing unnecessary benign biopsies.

Cintiligrafia cardíaca com metaiodobenzilguanidina marcada com iodo-123 em pacientes no estágio inicial da fase crônica da doença de chagas / Iodine-123 metaiodobenzylguadine cardiac scintigraphy in early estage of chaga's disease chronic phase

Objetivo: avaliar as alterações precoces da intervenção cardíaca autonômica simpática em pacientes assintomáticos, com eletrocardiograma (ECG) e ecocardiograma normais, apenas com diagnóstico sorológico de doença de Chagas. Métodos: 26 pacientes consecutivos com doença de chagas, com ECG e ecocardiograma normais, foram submetidos à cintilografia com metaiodobenzilguanidina marcada com Iodo-123 (Iodo 123 -MIBG). Foram excluídos pacientes com diabetes mellitus, arritmias, cardiopatias previas, doença de Parkinson, uso de simpaticomiméticos. Foram realizadas imagens planares do tórax aos 20 minutos e em 3 horas após a administração intravenosa de 259MBq do radiofármaco, bem como imagens tomográficas (SPECT) do tórax durante o estudo. Foram estabelecidas as relações...

Detecção e exérese de lesões mamárias não palpáveis orientadas por cirurgia radioguiada com injeção de ar para controle radiológico / Detection and excision of non-palpable breast lesions by radioguided surgery and air injection for radiological control

OBJETIVO: avaliar a eficiência da localização e exérese por cirurgia radioguiada de lesões ocultas mamárias utilizando radiofármaco injetado diretamente no interior das lesões ou até dois centímetros destas com posterior injeção de ar como controle radiológico. MÉTODOS: vinte e nove pacientes com 32 lesões mamárias ocultas, detectadas por mamografia ou ultra-sonografia, classificadas como Bi-Rads® 3, 4 e 5 foram incluídas neste estudo observacional com resultados expressos em percentagens. O radiofármaco utilizado foi o macroagregado de albumina marcado com tecnécio-99m (99mTc-MAA) injetado por orientação mamográfica ou guiado por ultra-sonografia. A injeção do radiofármaco foi seguida pela imediata administração de ar, através da agulha da estereotaxia, visando o controle radiológico da injeção do radiofármaco. A biopsia excisional foi feita com o auxílio do aparelho portátil gamma-probe (detector de radiação gama) e a remoção completa das lesões foi verificada pela radiografia das peças cirúrgicas ou por exame por congelação intra-operatório. RESULTADOS: câncer de mama foi encontrado em 10 por cento (1/10) das lesões BI-RADS® 3, em 31,5 por cento (6/19) das BI-RADS® 4 e em 66,6 por cento (2/3) das BI-RADS® 5. As 29 pacientes corresponderam a 32 espécimes, cirúrgicos. O radiofármaco foi corretamente posicionado em 96,8 por cento (31/32) dos espécimes permitindo remoção de 96,8 por cento das lesões mamárias não palpáveis estudadas. A completa remoção da lesão foi demonstrada pela radiografia das peças em 23 casos (71,8 por cento), pelo estudo intra-operatório por congelação em 21,8 por cento (7/32) e por ambos os métodos em 6,2 por cento (2/32). CONCLUSAO: a cirurgia radioguiada é importante instrumento na remoção de lesões mamárias não palpáveis, tratando-se de método simples, rápido e exeqüível que pode ser implementado na rotina clínica dessas pacientes.

Value of bone scintigraphy as a predictor method of mandibular growth: preliminary studies

The aim of this study was to evaluate the value of skeletal scintigraphy as a predictor method of mandibular growth. We studied 47 patients, both genders, from 18 to 24 years. Patients were divided in two groups classified, by Steiner cephalometric analysis, as Class I - control group (n=13) and Class III - study group (n=34). 99mTc-MDP (200 µCi/Kg) was injected and posterior images of lumbar spine and lateral right and left mandibular scans were obtained 2 hours after endovenous administration of the radiopharmaceutical. Regions of interest (ROI) were outlined on condyles and fourth lumbar vertebra. The average number of counts per pixel in each ROI was then determined and an uptake ratio of each mandibular region and the fourth lumbar vertebra was calculated. The t Student test was used for statistical analysis where no differences were observed between the groups, although a greater uptake was seen in condylar region in the study group. Skeletal scintigraphy showed to be an useful method to assess long bone and facial growth. However, further studies are now ongoing to increase the number of patients.

Avaliação de transplantes renais utilizando-se 99mTc-leucócitos mononucleares / Evaluation of renal allografts using 99mTc-mononuclear leukocytes

A rejeição aguda do enxerto renal deve ser diagnosticada precocemente, uma vez que a reversibilidade da rejeição está relacionada com a rapidez na qual o tratamento é iniciado. Os objetivos deste estudo foram: 1) estabelecer um método quantitativo para avaliação da rejeição e necrose tubular aguda (NTA) do rim transplantado; 2) determinar o papel em potencial da cintilografia com leucócitos mononucleares marcados com tecnécio-99m no diagnóstico precoce da rejeição do rim transplantado e no diagnóstico diferencial da NTA. Cento e sessenta estudos cintilográficos foram realizados no primeiro e no quinto dia pós-operatório em 80 pacientes transplantados. Células autólogas foram utilizadas para marcação. Imagens foram obtidas 30 minutos, 3 horas e 24 horas após injeção de 444 MBq (12 mCi) das células marcadas. Houve captação anormal das células marcadas em 27 de 31 casos de rejeição e em seis de oito casos de NTA. Os resultados foram comparados com a clínica de cada paciente. Ultra-sonografias com Doppler detectaram 18 de 31 casos de rejeição. A sensibilidade e a especificidade para rejeição foram, respectivamente, de 87,1 por cento e 100 por cento para a cintilografia e 58,1 por cento e 100 por cento para a ultra-sonografia. Foram realizadas biópsias em oito pacientes, que mostraram sete rejeições e uma NTA. Os resultados sugerem que a cintilografia com leucócitos mononucleares marcados com tecnécio-99m pode ser útil no diagnóstico de rejeição e diagnóstico diferencial de NTA.