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1.
Int Orthod ; 22(4): 100916, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39181039

RESUMEN

INTRODUCTION: Treatment of impacted upper incisors in a labially inverted position is challenging for orthodontists, and its prognosis has not been established in the literature. Thus, this systematic review aimed to determine the effectiveness and side effects of orthodontic traction of impacted maxillary incisors in a labially inverted position. METHODS: A comprehensive search was conducted in multiple databases, including MEDLINE (via PubMed), Scopus, Embase, Science Direct, and LILACS, up to June 30, 2024. Initially, 1640 articles were identified, and after applying specific selection criteria, 11 articles were selected for full-text evaluation. Following the review, only six studies were deemed relevant, comprising one before-and-after study, two longitudinal retrospective studies, and three cross-sectional studies. Newcastle-Ottawa and Risk of Bias (ROB-2) tools were used to assess the risk of bias in the selected studies. RESULTS: The average duration of traction for maxillary labially inverted impacted central incisors ranged from 8.60±1.26months to 18±6.0months, with all cases being successfully treated. Following traction, the clinical crown height of the incisors was significantly higher compared to the control group (P<0.01). Similarly, the root length of the impacted incisors after traction was shorter in the impaction group (approximately 2mm) compared to the control group. Likewise, the thickness of the alveolar bone varied among different studies. Some authors noted that the treatment group had a smaller thickness (about 0.5mm) compared to the control group (P<0.05), while other authors found similar thickness after treatment. CONCLUSIONS: Although there are few reported studies with a low risk of bias, it is clear that it is possible to successfully treat labially inverted impacted maxillary central incisors with apparently few side effects. Following traction, the clinical crown height of these incisors increased, while the root length was shorter than their normally erupted contralateral teeth.

2.
Radiography (Lond) ; 30(2): 628-633, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38330895

RESUMEN

INTRODUCTION: Computed tomography (CT) imaging has become indispensable in the management of medical oncology patients. Risks associated with high cumulative effective dose (CED) are relevant in testicular cancer patients. Split-bolus protocols, whereby the contrast medium injection is divided into two, followed by combining the required phase images in a single scan acquisition has been shown to provide images of comparable image quality and less radiation dose compared to single-bolus split-phase CT for various indications. We retrospectively evaluated the performance of split-bolus and single-bolus protocols in patients having follow-up CT imaging for testicular cancer surveillance. METHODS: 45 patients with testicular cancer undergoing surveillance CT imaging of the thorax, abdomen, and pelvis who underwent split-bolus and single-bolus protocols were included. Quantitative image quality analysis was conducted by placing region of interests in pre-defined anatomical sub-structures within the abdominal cavity. The signal-to-noise ratio (SNR) and radiation dose in the form of dose length product (DLP) and effective dose (ED) were recorded. RESULTS: The DLP and ED for the single-bolus, split-phase acquisition was 506 ± 89 mGy cm and 7.59 ± 1.3 mSv, respectively. For the split-bolus, single-phase acquisition, 397 ± 94 mGy∗cm and 5.95 ± 1.4 mSv, respectively (p < 0.000). This represented a 21.5 % reduction in radiation dose exposure. The SNR for liver, muscle and fat for the single-bolus were 7.4, 4.7 and 8, respectively, compared to 5.5, 3.8 and 7.4 in the split-bolus protocol (p < 0.001). CONCLUSION: In a testicular cancer patient cohort undergoing surveillance CT imaging, utilization of a split-bolus single-phase acquisition CT protocol enabled a significant reduction in radiation dose whilst maintaining subjective diagnostic acceptability. IMPLICATIONS FOR PRACTICE: Use of split-bolus, single-phase acquisition has the potential to reduce CED in surveillance of testicular cancer patients.


Asunto(s)
Neoplasias de Células Germinales y Embrionarias , Neoplasias Testiculares , Masculino , Humanos , Estudios Retrospectivos , Neoplasias Testiculares/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Medios de Contraste
6.
Radiol Bras ; 54(3): 193-197, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34108767

RESUMEN

Parathyroid adenoma is the most common cause of primary hyperparathyroidism. Advances in surgical techniques have made it possible to excise only the affected parathyroid gland in most cases. Imaging examinations play a fundamental role in the preoperative planning of parathyroidectomy. To localize the parathyroid glands, imaging tests such as scintigraphy, ultrasound, and, more recently, four-dimensional computed tomography (4D CT). The aim of this pictorial review was to illustrate the use of the 4D CT protocol in cases of parathyroid adenoma and to determine how well it correlates with other imaging methods, in order to improve understanding of the 4D CT method.


O adenoma de paratireoide é a causa mais comum de hiperparatireoidismo primário. Com o avanço das técnicas cirúrgicas, na maioria das vezes é realizada a retirada apenas da paratireoide afetada. Para que isso seja possível, os exames de imagem têm papel fundamental. São utilizados para a localização das paratireoides exames como a cintilografia e a ultrassonografia, e recentemente a tomografia computadorizada quadridimensional (TC 4D) com protocolo específico. O objetivo deste ensaio é descrever o uso do protocolo TC 4D em casos de adenoma da paratireoide e determinar sua correlação com os outros métodos de imagem, para facilitar o entendimento do método.

7.
Radiol. bras ; Radiol. bras;54(3): 193-197, May-June 2021. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1250665

RESUMEN

Abstract Parathyroid adenoma is the most common cause of primary hyperparathyroidism. Advances in surgical techniques have made it possible to excise only the affected parathyroid gland in most cases. Imaging examinations play a fundamental role in the preoperative planning of parathyroidectomy. To localize the parathyroid glands, imaging tests such as scintigraphy, ultrasound, and, more recently, four-dimensional computed tomography (4D CT). The aim of this pictorial review was to illustrate the use of the 4D CT protocol in cases of parathyroid adenoma and to determine how well it correlates with other imaging methods, in order to improve understanding of the 4D CT method.


Resumo O adenoma de paratireoide é a causa mais comum de hiperparatireoidismo primário. Com o avanço das técnicas cirúrgicas, na maioria das vezes é realizada a retirada apenas da paratireoide afetada. Para que isso seja possível, os exames de imagem têm papel fundamental. São utilizados para a localização das paratireoides exames como a cintilografia e a ultrassonografia, e recentemente a tomografia computadorizada quadridimensional (TC 4D) com protocolo específico. O objetivo deste ensaio é descrever o uso do protocolo TC 4D em casos de adenoma da paratireoide e determinar sua correlação com os outros métodos de imagem, para facilitar o entendimento do método.

9.
Tex Heart Inst J ; 47(2): 78-85, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-32603460

RESUMEN

Assessing thromboembolic risk is crucial for proper management of patients with atrial fibrillation. Left atrial volume is a promising predictor of cardiac thrombosis. To determine whether left atrial volume can predict left atrial appendage thrombus in patients with atrial fibrillation, we conducted a prospective study of 73 patients. Left atrial and ventricular volumes were evaluated by cardiac computed tomography with retrospective electrocardiographic gating and then indexed to body surface area. Left atrial appendage thrombus was confirmed or excluded by cardiac computed tomography with delayed enhancement. Seven patients (9.6%) had left atrial appendage thrombus; 66 (90.4%) did not. Those with thrombus had a significantly higher mean left atrial end-systolic volume index (139 ± 55 vs 101 ± 35 mL/m2; P =0.0097) and mean left atrial end-diastolic volume index (122 ± 45 vs 84 ± 34 mL/m2; P =0.0077). On multivariate logistic regression analysis, left atrial end-systolic volume index (per 10 mL/m2 increase) was significantly associated with left atrial appendage thrombus (odds ratio [OR]=1.24; 95% CI, 1.03-1.50; P =0.02); so too was the left atrial end-diastolic volume index (per 10 mL/m2 increase) (OR=1.29; 95% CI, 1.05-1.60; P =0.02). These findings suggest that increased left atrial volume increases the risk of left atrial appendage thrombus. Therefore, patients with atrial fibrillation and an enlarged left atrium should be considered for cardiac computed tomography with delayed enhancement to confirm whether thrombus is present.


Asunto(s)
Apéndice Atrial , Volumen Cardíaco/fisiología , Cardiopatías/diagnóstico , Trombosis/diagnóstico , Tomografía Computarizada por Rayos X/métodos , Anciano , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Femenino , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/fisiopatología , Cardiopatías/etiología , Cardiopatías/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos
10.
Int. j. cardiovasc. sci. (Impr.) ; 33(1): 87-93, Jan.-Feb. 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1090637

RESUMEN

Abstract 18-fluorine-fluorodeoxyglucose positron emission computed tomography (18F-FDG PET/CT) and singlephoton emission computed tomography (SPECT) using radiolabeled white blood cells (WBC) are non-invasive techniques widely used in the diagnosis of infections, like endocarditis. The aim of our paper was to provide a systematic review of the published data on the use of 18F-FDG PET/CT and SPECT in infective endocarditis (IE). A comprehensive literature search of the PubMed/ MEDLINE, Scopus, Embase and Cochrane library databases was conducted to find relevant published articles about the diagnostic performance of SPECT using WBC and 18F-FDG PET/CT in the diagnosis of infectious endocarditis. Twenty papers were included, with a total of 1,154 patients (166 studies with WBC SPECT and 988 with 18F-FDG PET/CT). From the analyses of the studies, the following results were obtained: both SPECT and PET/CT had good diagnostic accuracy in the study of endocarditis. 18F-FDG PET/CT had good specificity (85.8%) and lower sensitivity (68%), with high heterogeneity among the studies; WBC SPECT/ CT had an overall sensitivity of 80% and specificity of 98%. Specific preparations for PET/CT can affect the diagnostic accuracy of the test. Both 18F-FDG PET/CT and WBC SPECT are useful for the diagnosis of IE, and WBC SPECT appears to be slightly more specific than 18F-FDG PET/CT. A specific diet could influence the diagnostic performance of PET/CT.


Asunto(s)
Humanos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Endocarditis/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Implantación de Prótesis de Válvulas Cardíacas , Leucocitos
11.
Acad Radiol ; 27(9): 1249-1254, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-31843393

RESUMEN

RATIONALE AND OBJECTIVES: To evaluate the image quality and suitability of Dual-Source Dual-Energy CT venography (DSDE-CTV) with asynchronous virtual monoenergetic images (VMI+) of the entire lower extremity in the context of pre-surgical assessment of complex cases prior to coronary bypass graft as a feasibility study. MATERIALS AND METHODS: Fifteen consecutive patients, consisting of 5 females and 10 males with an average age of 52 ± 17 years underwent DSDE-CTV from the pubic symphysis to the ankles after intravenous injection of an iodinated contrast medium. DSDE-CTV was acquired with tube voltages of 80 kVp and sn140 kVp. Single spectrum images (A - 80 kVp; B - 140 kVp) as well as a linearly blended mixed data set (M_0.6) were reconstructed. By postprocessing, an VMI+ dataset at 40 keV was generated. Objective image quality parameters of the deep and superficial veins of thigh, knee, and calves were measured separately for each location. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Additionally, subjective image quality was assessed independently by two radiologists. RESULTS: Mean vascular attenuation was 73.9 ± 17.8 HU at B, 113.7 ± 42.2 HU at M_0.6, 119.4 ± 45.5 HU at A, and 201.0 ± 89.7 HU at VMI+. Mean CNR was 6.7 ± 2.0 at 140 keV, 9.25 ± 2.3 in the M_0.6 datasets, 8.7 ± 3.0 at 80 keV, and 12.9 ± 4.3 at 40 keV. Attenuation values were approximately doubled when compared to the reference standard (M_0.6) with significantly improved SNR and CNR (p < 0.05). Subjective image quality scores were highest for VMI+ datasets (4.1 ± 0.5) and lowest for B datasets (2.3 ± 0.37), however differences between VMI+ datasets and M_0.6 datasets did not reach statistical significance. CONCLUSION: Postprocessing of dual-energy CTV with VMI+ significantly increases attenuation of veins and markedly improves SNR and CNR values, thereby improving the diagnostic quality of CTV for the evaluation of deep and superficial veins of the entire lower limb prior to coronary bypass graft.


Asunto(s)
Imagen Radiográfica por Emisión de Doble Fotón , Adulto , Anciano , Animales , Bovinos , Puente de Arteria Coronaria , Estudios de Factibilidad , Femenino , Humanos , Extremidad Inferior/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Flebografía , Interpretación de Imagen Radiográfica Asistida por Computador , Estudios Retrospectivos , Relación Señal-Ruido
12.
Radiol Bras ; 51(2): 76-80, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29743733

RESUMEN

OBJECTIVE: To compare the degree of benign bone marrow uptake of 18F-fluorodeoxyglucose (18F-FDG) between Hodgkin lymphoma patients with and without B symptoms. MATERIALS AND METHODS: We analyzed the medical charts of 74 Hodgkin lymphoma patients who underwent 18F-FDG positron emission tomography/computed tomography (PET/CT) prior to the initiation of therapy between October 2010 and September 2013. In all of the patients, the bone marrow biopsy was negative and the 18F-FDG PET/CT images did not suggest bone marrow involvement. Of the 74 patients evaluated, 54 presented inflammatory (B) symptoms and 20 did not. Regions of interest (ROIs) were drawn on the sternum, the proximal thirds of the humeri, the proximal thirds of the femora, and both iliac wings (totaling seven ROIs per patient). To compare the patients with and without B symptoms, in terms of standardized uptake values (SUVs) for the seven ROIs, we used the Mann-Whitney U test. RESULTS: For six of the ROIs, the SUVs were higher in the patients with B symptoms than in those without, and the difference was statistically significant (p < 0.05). There was also a tendency toward a statistically significant difference between the two groups in terms of the SUV for the right iliac wing ROI (p = 0.06). CONCLUSION: In our sample, the presence of B symptoms was associated with increased 18F-FDG uptake in bone marrow.


OBJETIVO: Comparar o grau de absorção benigna de 18F-fluordesoxiglicose (18F-FDG) na medula óssea de pacientes com linfoma de Hodgkin com e sem sintomas B. MATERIAIS E MÉTODOS: Analisamos os prontuários de 74 pacientes com linfoma de Hodgkin submetidos a tomografia por emissão de pósitrons/tomografia computadorizada (PET/CT) com 18F-FDG antes do início da terapia entre outubro de 2010 e setembro de 2013. Em todos os pacientes, a biópsia da medula óssea foi negativa e as imagens de 18F-FDG PET/CT não sugeriram envolvimento da medula óssea. Dos 74 pacientes avaliados, 54 apresentaram sintomas inflamatórios (B) e 20 não. As regiões de interesse (ROIs) foram desenhadas no esterno, nos terços proximais dos úmeros, nos terços proximais dos fêmures e nas duas asas ilíacas (totalizando sete ROIs por paciente). Para comparar os pacientes com e sem sintomas B, em termos dos standardized uptake values (SUVs) para as sete ROIs, utilizamos o teste U de Mann-Whitney. RESULTADOS: Para seis das ROIs, os SUVs foram maiores nos pacientes com sintomas B do que nos pacientes sem, e a diferença foi estatisticamente significante (p < 0,05). Houve também tendência para uma diferença estatisticamente significante entre os dois grupos em termos do SUV para a ROI da asa ilíaca direita (p = 0,06). CONCLUSÃO: Na nossa amostra, a presença de sintomas B foi associada ao aumento da captação de 18F-FDG na medula óssea.

13.
Radiol. bras ; Radiol. bras;51(2): 78-80, Mar.-Apr. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-956238

RESUMEN

Abstract Objective: To compare the degree of benign bone marrow uptake of 18F-fluorodeoxyglucose (18F-FDG) between Hodgkin lymphoma patients with and without B symptoms. Materials and Methods: We analyzed the medical charts of 74 Hodgkin lymphoma patients who underwent 18F-FDG positron emission tomography/computed tomography (PET/CT) prior to the initiation of therapy between October 2010 and September 2013. In all of the patients, the bone marrow biopsy was negative and the 18F-FDG PET/CT images did not suggest bone marrow involvement. Of the 74 patients evaluated, 54 presented inflammatory (B) symptoms and 20 did not. Regions of interest (ROIs) were drawn on the sternum, the proximal thirds of the humeri, the proximal thirds of the femora, and both iliac wings (totaling seven ROIs per patient). To compare the patients with and without B symptoms, in terms of standardized uptake values (SUVs) for the seven ROIs, we used the Mann-Whitney U test. Results: For six of the ROIs, the SUVs were higher in the patients with B symptoms than in those without, and the difference was statistically significant (p < 0.05). There was also a tendency toward a statistically significant difference between the two groups in terms of the SUV for the right iliac wing ROI (p = 0.06). Conclusion: In our sample, the presence of B symptoms was associated with increased 18F-FDG uptake in bone marrow.


Resumo Objetivo: Comparar o grau de absorção benigna de 18F-fluordesoxiglicose (18F-FDG) na medula óssea de pacientes com linfoma de Hodgkin com e sem sintomas B. Materiais e Métodos: Analisamos os prontuários de 74 pacientes com linfoma de Hodgkin submetidos a tomografia por emissão de pósitrons/tomografia computadorizada (PET/CT) com 18F-FDG antes do início da terapia entre outubro de 2010 e setembro de 2013. Em todos os pacientes, a biópsia da medula óssea foi negativa e as imagens de 18F-FDG PET/CT não sugeriram envolvimento da medula óssea. Dos 74 pacientes avaliados, 54 apresentaram sintomas inflamatórios (B) e 20 não. As regiões de interesse (ROIs) foram desenhadas no esterno, nos terços proximais dos úmeros, nos terços proximais dos fêmures e nas duas asas ilíacas (totalizando sete ROIs por paciente). Para comparar os pacientes com e sem sintomas B, em termos dos standardized uptake values (SUVs) para as sete ROIs, utilizamos o teste U de Mann-Whitney. Resultados: Para seis das ROIs, os SUVs foram maiores nos pacientes com sintomas B do que nos pacientes sem, e a diferença foi estatisticamente significante (p < 0,05). Houve também tendência para uma diferença estatisticamente significante entre os dois grupos em termos do SUV para a ROI da asa ilíaca direita (p = 0,06). Conclusão: Na nossa amostra, a presença de sintomas B foi associada ao aumento da captação de 18F-FDG na medula óssea.

14.
Emerg Radiol ; 25(4): 367-374, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29478119

RESUMEN

PURPOSE: The purpose of this study was to review and compare the image quality and radiation dose of split-bolus single-pass computed tomography(CT) in the assessment of trauma patients in comparison to standard multi-phase CT techniques. METHODS: An online electronic database was searched using the MESH terms "split-bolus," "dual phase," and "single pass." Inclusion criteria required the research article to compare a split contrast bolus protocol in a single-pass scan in the assessment of trauma patients. Studies using split-bolus CT technique in non-traumatic injury assessment were excluded. Six articles met the inclusion criteria. CONCLUSIONS: Parenchymal and vascular image qualities, as well as subjective image quality assessments, were equal or superior in comparison to non-split-bolus multi-phase trauma CT protocols. Split-bolus single-pass CT decreased radiation exposure in all studies. Further research is required to determine the superior split-bolus protocol and the specificity and sensitivity of detecting blunt cerebrovascular injury screening, splenic parenchymal vascular lesions, and characterization of pelvic vascular extravasation.


Asunto(s)
Traumatismo Múltiple/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Medios de Contraste , Humanos , Sensibilidad y Especificidad , Imagen de Cuerpo Entero
15.
Clin Physiol Funct Imaging ; 34(5): 340-55, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24289258

RESUMEN

Lung cancer represents an increasingly frequent cancer diagnosis worldwide. An increasing awareness on smoking cessation as an important mean to reduce lung cancer incidence and mortality, an increasing number of therapy options and a steady focus on early diagnosis and adequate staging have resulted in a modestly improved survival. For early diagnosis and precise staging, imaging, especially positron emission tomography combined with CT (PET/CT), plays an important role. Other functional imaging modalities such as dynamic contrast-enhanced CT (DCE-CT) and diffusion-weighted MR imaging (DW-MRI) have demonstrated promising results within this field. The purpose of this review is to provide the reader with a brief and balanced introduction to these three functional imaging modalities and their current or potential application in the care of patients with lung cancer.


Asunto(s)
Diagnóstico por Imagen/métodos , Neoplasias Pulmonares/diagnóstico , Imagen de Difusión por Resonancia Magnética , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Imagen Multimodal , Estadificación de Neoplasias , Tomografía de Emisión de Positrones , Valor Predictivo de las Pruebas , Tomografía Computarizada por Rayos X
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