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1.
In Vivo ; 36(1): 206-211, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34972716

RESUMO

BACKGROUND/AIM: This study performed 99mTc-MAG3 renal scintigraphy on rabbit kidneys and evaluated its ability to identify obstructive or non-obstructive kidneys. MATERIALS AND METHODS: Renal function was assessed during a four-week post-obstruction period by obtaining planar images of 99mTc-MAG3 activity following an ear vein injection. The individual renal function was evaluated by renal scintigraphy in conjunction with histopathological and morphological examinations. RESULTS: The renal perfusion of 99mTc-MAG3 in the right kidney with a ureteral obstruction decreased with time. The width, height, and cortical thickness of the obstructed right kidney were significantly larger than those of the left kidney. A histopathological examination four weeks after the ureteral obstruction revealed a typical pattern of urinary tract obstruction, including multiple tubules, enlargement of the interstitial area, and cytoplasmic vacuoles. CONCLUSION: 99mTc-MAG3 renal scintigraphy provides the kidney shape and size and can identify potential obstructive and non-obstructive kidneys in rabbits.


Assuntos
Renografia por Radioisótopo , Obstrução Ureteral , Animais , Rim/diagnóstico por imagem , Rim/fisiologia , Coelhos , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Mertiatida , Obstrução Ureteral/diagnóstico por imagem
2.
PLoS One ; 16(7): e0253609, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34214103

RESUMO

BACKGROUND: Studies have reported agreement between computed tomography (CT) and renography for the determination of split kidney function. However, their correlation with post-donation kidney function remains unclear. We compared CT measurements with renography in assessment of split kidney function (SKF) and their correlations with post-donation kidney function. METHODS: A single-centre, retrospective cohort study of 248 donors from January 1, 2009-July 31, 2019 were assessed. Pearson correlations were used to assess post-donation kidney function with renography and CT-based measurements. Furthermore, we examined high risk groups with SKF difference greater than 10% on renography and donors with post-donation eGFR less than 60 mL/min/1.73m2. RESULTS: 62% of donors were women with a mean (standard deviation) pre-donation eGFR 99 (20) and post-donation eGFR 67 (22) mL/min/1.73m2 at 31 months of follow-up. Post-donation kidney function was poorly correlated with both CT-based measurements and renography, including the subgroup of donors with post-donation eGFR less than 60 mL/min/1.73m2 (r less than 0.4 for all). There was agreement between CT-based measurements and renography for SKF determination (Bland-Altman agreement [bias, 95% limits of agreement] for renography vs: CT volume, 0.76%, -7.60-9.15%; modified ellipsoid,1.01%, -8.38-10.42%; CC dimension, 0.44%, -7.06-7.94); however, CT missed SKF greater than 10% found by renography in 20 out 26 (77%) of donors. CONCLUSIONS: In a single centre study of 248 living donors, we found no correlation between CT or renography and post-donation eGFR. Further research is needed to determine optimal ways to predict remaining kidney function after donation.


Assuntos
Transplante de Rim , Rim/fisiologia , Doadores Vivos/estatística & dados numéricos , Nefrectomia/efeitos adversos , Coleta de Tecidos e Órgãos/efeitos adversos , Adulto , Feminino , Seguimentos , Taxa de Filtração Glomerular/fisiologia , Humanos , Rim/diagnóstico por imagem , Testes de Função Renal/métodos , Testes de Função Renal/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Renografia por Radioisótopo/estatística & dados numéricos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/estatística & dados numéricos
3.
MAGMA ; 34(6): 805-822, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34160718

RESUMO

INTRODUCTION: Model-driven registration (MDR) is a general approach to remove patient motion in quantitative imaging. In this study, we investigate whether MDR can effectively correct the motion in free-breathing MR renography (MRR). MATERIALS AND METHODS: MDR was generalised to linear tracer-kinetic models and implemented using 2D or 3D free-form deformations (FFD) with multi-resolution and gradient descent optimization. MDR was evaluated using a kidney-mimicking digital reference object (DRO) and free-breathing patient data acquired at high temporal resolution in multi-slice 2D (5 patients) and 3D acquisitions (8 patients). Registration accuracy was assessed using comparison to ground truth DRO, calculating the Hausdorff distance (HD) between ground truth masks with segmentations and visual evaluation of dynamic images, signal-time courses and parametric maps (all data). RESULTS: DRO data showed that the bias and precision of parameter maps after MDR are indistinguishable from motion-free data. MDR led to reduction in HD (HDunregistered = 9.98 ± 9.76, HDregistered = 1.63 ± 0.49). Visual inspection showed that MDR effectively removed motion effects in the dynamic data, leading to a clear improvement in anatomical delineation on parametric maps and a reduction in motion-induced oscillations on signal-time courses. DISCUSSION: MDR provides effective motion correction of MRR in synthetic and patient data. Future work is needed to compare the performance against other more established methods.


Assuntos
Imageamento por Ressonância Magnética , Renografia por Radioisótopo , Algoritmos , Humanos , Espectroscopia de Ressonância Magnética , Movimento (Física) , Respiração
4.
Nucl Med Commun ; 42(6): 602-610, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33625182

RESUMO

INTRODUCTION: In 1978, O'Reilly introduced the diuretic renogram using the F + 20 method. Initially, the patient was examined in the seated position. A dose of 40 mg furosemide was injected intravenously 20 min following tracer injection and dynamic acquisition was prolonged for 15-20 min. In 1992, the guidelines suggested to study patients in the supine position to avoid risk of diuretic-induced hypotension and reduce patient movement. Unfortunately, equivocal findings were reported in 15-30% of cases. Side effects such as bladder fullness and disruption because of voiding were reported. Several methods had been proposed in the supine position, such as the well-tempered diuretic renogram F + 20, F - 15, F0 and F + 2, with different time in minute of diuretic administration in relation to tracer injection. However, as confirmed by many studies, there was no clear evidence suggesting superiority among these methods. We suggest using the diuretic renogram with the F ± 10(sp) method for the diagnosis of obstruction in adult patients with hydronephrosis and for the follow-up in patients who underwent a surgical treatment of the urinary tract. METHODS: We searched all international guidelines and articles of most influential authors published from 1978 to October 2020 on diuretic renogram. RESULTS: We selected 60 articles. DISCUSSION: F + 10(sp) method improves patient compliance avoiding bladder fullness-related problems, without need of catheterization. It allows for a more reliable quantification of the renal output, thanks to outflow indices that are favored by gravity effects.


Assuntos
Diuréticos , Renografia por Radioisótopo , Postura Sentada , Adulto , Furosemida , Humanos , Tecnécio Tc 99m Mertiatida , Obstrução Ureteral
5.
Nefrología (Madrid) ; 41(1): 27-33, ene.-feb. 2021. graf, tab
Artigo em Inglês | IBECS | ID: ibc-199570

RESUMO

BACKGROUND: Glomerular filtration rate (GFR) is a useful index in many clinical conditions. However, very few studies have assessed the performance of full age spectrum (FAS) equation and the Asian modified Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation in the approximation of GFR in Chinese patients with chronic kidney disease. OBJECTIVE: This study aimed to compare the diagnostic performance of the above two creatinine-based equations. METHODS: A well designed single-center cross-sectional study was performed and the GFR was determined by 3 methods separately in the same day: technetium-99m-diethylene triamine pentaacetic acid (99mTc-DTPA) dual plasma sample clearance method (mGFR); FAS equation method; Asian modified CKD-EPI equation method. The gold standard method was the mGFR. Equations performance criteria considered correlation coefficient, bias, precision, accuracy and the ability to detect the mGFR less than 60 ml/min/1.73 m2. RESULTS: A total of 160 patients were enrolled. The diagnostic performance of FAS showed no significant difference in the correlation coefficient (0.89 vs 0.89), precision (15.9 vs 16.1 ml/min/1.73 m2), accuracy (75.0% vs 76.3%) and the ability to detect the mGFR less than 60ml/min/1.73m2 (0.94 vs 0.94) compared with the Asian modified CKD-EPI equation in all participants. The FAS showed a negative bias, while the new CKD-EPI equation showed a positive bias (-1.20 vs 1.30 ml/min/1.73 m2, P < 0.001). However, they were all near to zero. In the mGFR < 60 ml/min/1.73 m2 subgroup and mGFR > 60 ml/min/1.73 m2 subgroup were consistent with that in the whole cohort. The precision and accuracy decreased when GFR > 60 ml/min/1.73 m2 in both equations. CONCLUSIONS: The FAS equation and the Asian modified CKD-EPI equation had similar performance in determining the glomerular filtration rate in the Chinese patients with chronic kidney disease. Both the FAS equation and Asian modified CKD-EPI can be a satisfactory method and may be the most suitable creatinine-based equation


ANTECEDENTES: La tasa de filtración glomerular (TFG) es un índice útil en muchas condiciones clínicas. Sin embargo, muy pocos estudios han evaluado el rendimiento de la ecuación FAS (full age spectrum) y la ecuación CKD-EPI (Chronic Kidney Disease-Epidemiology Collaboration) modificada para Asia en la aproximación de TFG en pacientes chinos con enfermedad renal crónica. OBJETIVO: El objetivo de este estudio fue comparar el rendimiento diagnóstico de las dos ecuaciones anteriores basadas en creatinina. MÉTODOS: Se realizó un estudio transversal unicéntrico y bien diseñado, calculándose separadamente la TFG mediante tres métodos en el mismo día: método mGFR (aclaramiento de muestra de plasma dual con 99mTc-DTPA [tecnecio-99m marcado con triamina dietileno de ácido pentaacético]), el método de ecuación FAS y el de ecuación CKD-EPI modificada para Asia. El método de referencia fue mGFR. Los criterios de rendimiento de las ecuaciones consideraron coeficiente de correlación, sesgo, precisión, exactitud y capacidad de detectar un valor de mGFR inferior a 60 mL/min/1,73 m2. RESULTADOS: Se incluyó un total de 160 pacientes. El rendimiento diagnóstico de FAS no reflejó diferencia significativa en cuanto a coeficiente de correlación (0,89 vs. 0,89), precisión (15,9 vs. 16,1 mL/min/1,73 m2), exactitud (75 vs. 76,3%) y capacidad de detectar un valor de mGFR inferior a 60 mL/min/1,73 m2 (0,94 vs. 0,94) en comparación con la ecuación CKD-EPI modificada para Asia, en todos los participantes. La ecuación FAS reflejó un sesgo negativo, mientras que la nueva ecuación CKD-EPI reflejó un sesgo positivo (-1,20 V vs.1,30 mL/min/1,73 m2, p < 0,001). Sin embargo, todos los valores se aproximaron a cero. En el subgrupo mGFR < 60 mL/min/1,73 m2 y el subgrupo mGFR > 60 mL/min/1,73 m2 los valores fueron consistentes con respecto a la cohorte total. La precisión y exactitud se redujeron cuando TFG > 60 mL/min/1,73 m2 en ambas ecuaciones. CONCLUSIONES: La ecuación FAS y la ecuación CKD-EPI modificada para Asia reflejaron un desempeño similar a la hora de determinar la tasa de filtración glomerular en los pacientes chinos con enfermedad renal crónica. Ambos pueden ser métodos satisfactorios y las ecuaciones más idóneas basadas en creatinina


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Insuficiência Renal Crônica/diagnóstico , Pentetato de Tecnécio Tc 99m/farmacocinética , Taxa de Filtração Glomerular , Creatinina/sangue , Insuficiência Renal Crônica/sangue , Plasma/efeitos da radiação , Grupo com Ancestrais do Continente Asiático/estatística & dados numéricos , Estudos Transversais , Renografia por Radioisótopo/métodos , Insuficiência Renal Crônica/diagnóstico por imagem , Protocolos Clínicos , China
6.
Nucl Med Rev Cent East Eur ; 23(2): 53-57, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33007090

RESUMO

BACKGROUND: Dynamic renal scintigraphy remains the recognized method for evaluation of kidney function and perfusion. Although there is an extensive body of knowledge about the use of technetium-99m-mercaptoacetyltriglycine (99mTc-MAG3), much less has been written about renal technetium-99m-ethylenedicysteine (99mTc-EC) scintigraphy. The aim of this study was to determine the normal value of renal function parameters in 99mTc-EC dynamic renal scintigraphy: Tmax and T1/2. The effects of age, left or right side in the retroperitoneal space, and sex on those parameters were examined. MATERIAL AND METHODS: The research was conducted on 123 patients (F/M: 70/53; aged 2-71; averaging 14.8 years of age) with at least one normal kidney. A total of 194 healthy kidneys were examined, including pediatric kidneys. RESULTS: According to this study, the normal value of Tmax is 2.85 min (± 1.16) and T1/2 is 8.7 min (± 3.61). Values calculated for pediatric studies are Tmax is 2.81 (± 1.16) and T1/2 is 8.63 (± 3.71). CONCLUSIONS: The normal value of secretory and excretory renal function parameters was calculated. Although the value is slightly lower for children, this is not statistically significant, as globally there are no differences between the kidney-location sides and sexes for any parameter.


Assuntos
Cisteína/análogos & derivados , Testes de Função Renal/normas , Compostos de Organotecnécio , Renografia por Radioisótopo/normas , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Adulto Jovem
7.
Nucl Med Rev Cent East Eur ; 23(2): 78-83, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33007094

RESUMO

BACKGROUND: One of the basic clinical indications for dynamic renal scintigraphy (DRS) is a diagnosis of obstructive uropathy and/or nephropathy. Currently, a basic quantitative criterion for diagnosing nephropathy is the percentage of individual kidney's contribution in the global uptake of a radiopharmaceutical from the blood (so-called Split Function - SF). From a clinical point of view, a parameter evaluating a radiopharmaceutical uptake and reflecting the efficiency of a specific kidney, determined independently of the total uptake of both kidneys, would be much more useful. Based on a Rutland theory, a kidney uptake constant K proportional to a radiotracer uptake by individual kidney was introduced and applied to DRS with 99mTc-ethylene-1-dicysteine (99mTc-EC). In addition, a kidney efficiency index (KEi) was also worked out as a new parameter obtained by dividing the uptake constant K by the surface of the ROI of a given kidney, which can be interpreted as the average "efficiency" of clearance of a kidney. MATERIAL AND METHODS: K and KEi values were verified in 72 studies selected retrospectively from patients referred routinely for DRS, with available current level of blood creatinine, used for calculation of estimated GFR (eGFR) according to a CKD-EPI formula. After splitting of eGFR values into individual kidneys according to SF, single kidney eGFR values (SKeGFR) were obtained and then used as a verification method for SF, K and KEi values. RESULTS: Correlation between SF and SKeGFR values, rsp = 0.64, was significantly weaker (p < 0.0022) than the correlation of SKeGFR values with K uptake constants and KEi indices: 0.90 and 0.84, respectively. CONCLUSIONS: Uptake constant K and KEi, as quantitative parameters, give the opportunity to analyze a function of each kidney separately and in an absolute way. KEi also allows for a reliable assessment of kidneys of atypical sizes (larger or smaller than average). It also gives the opportunity to create normative values for this parameter and may be useful in a number of clinical situations where the diagnostic effectiveness of such a relative parameter as SF, is severely limited, e.g. in assessing a large kidney with hydronephrosis or while differing a cirrhotic from hypoplastic (i.e. a small but properly functioning) kidney.


Assuntos
Rim/diagnóstico por imagem , Rim/metabolismo , Renografia por Radioisótopo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transporte Biológico , Feminino , Humanos , Rim/fisiologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Nucl Med Rev Cent East Eur ; 23(2): 84-88, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33007095

RESUMO

BACKGROUND: One of the main indications for DRS is a diagnosis of obstructive uro-/nephropathy. In standard practice, this study includes the assessment of sequential scintigraphic images, renographic curves and such quantitative parameters as TMAX, T1/2 and split function of each kidney (SF). Due to the relative nature of SF and limitations of diagnostic capabilities of TMAX and T1/2, DRS was expanded to include new quantitative parameters describing kidney function in absolute values. This study aims to evaluate the usefulness of kidney efficiency index (KEi) - new, in-house developed parameter proportional to the average clearance function of the kidney. MATERIAL AND METHODS: The study included 156 people aged 18-84 (average 51) years. The first group, from which normative values of new parameters were determined, consisted of 20 healthy volunteers. The second group consisted of 136 patients selected retrospectively, based on archived scintigraphic data. "Normalcy rate" (percentage of normal results among selected 62 patients with a low likelihood of obstructive uro-/nephropathy) was used to evaluate the reliability of KEi. A comparative differential analysis of obstructive uro-/nephropathy, based on standard and new DRS parameters, was performed on selected 74 patients (92 kidneys) with single functioning kidney or bilateral obstructive uropathy, where SF is unreliable. RESULTS: Normative values: KEi ≥ 8; Normalcy rate for KEi: 95%. In comparison with standard DRS evaluation, application of KEi changed the diagnosis in 1/3 of assessed kidneys (from uropathy to nephropathy in 27/92 kidneys and vice versa in 4 kidneys). CONCLUSIONS: KEi enables reproducible, quantitative assessment of absolute kidney function without any modifications of the standard DRS protocol. Its values can be compared between independent studies (e.g. follow-up examinations). KEi corrected the diagnosis of obstructive uro-/nephropathy in cases of single functioning kidney or bilateral obstructive uropathy.


Assuntos
Nefropatias/diagnóstico por imagem , Nefropatias/fisiopatologia , Rim/diagnóstico por imagem , Rim/fisiopatologia , Renografia por Radioisótopo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transporte Biológico , Feminino , Humanos , Rim/metabolismo , Nefropatias/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
9.
Nucl Med Rev Cent East Eur ; 23(2): 89-96, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33007096

RESUMO

BACKGROUND: Ionizing radiation is a strong stimulator of reactive oxygen specises (ROS) and reactive nitrogen species (RNS). These reactive species may cause oxidative and nitrosative stress. In this study, we aimed to evaluate possible effects of 99mTechnetium (99mTc)-methoxyisobuthylisonitrite (MIBI), 99mTc-dimercaptosuccinic acid (DMSA), 99mTc-mercaptoacetyltriglycine (MAG-3) on oxidative and nitrosative stress biomarkers in patients who were performed myocardial perfusion scintigraphy (MPS) and renal scintigraphy. MATERIAL AND METHODS: Patients (n = 29) who were referred to nuclear medicine department were chosen as the patient group. They were divided into three subgroups according to the type of disease and 99mTc labelled agent. The first patient group had MPS (n = 9). The second patient group had 99mTc-DMSA renal scintigraphy (n = 12). The third patient group had 99mTc-MAG-3 renal scintigraphy (n = 8). The blood samples were taken from first, second and third patient groups 1 h, 3 h, 45 min after injection of the agent, respectively. The samples were taken from healthy volunteers (n = 25) as a control group. Alterations in catalase (CAT),superoxide dismutase (SOD), malondialdehyde (MDA) levels as oxidative stress biomarkers and nitric oxide (NO) and 3-Nitrotyrosine (3-NTx) levels as nitrosative stress biomarkers in all blood samples were evaluated. RESULTS: Results of MPS and renal scintigraphy performed patients were compared with control group separately. CAT, SOD, MDA and 3-NTx levels were higher in the first group than the control group (p < 0.05). Although NO levels were higher in the first group than the control group, it was not statistically significant (p > 0.05). CAT and SOD levels were lower in second and third groups than the control group (p < 0.0 5). However, MDA, NO, 3-NTx levels were higher in second and third groups than the control group (p < 0.05). CONCLUSIONS: These results show that oxidative and nitrosative balance is impaired due to ionization radiation. These reactive species might stimulate an adaptive and protective cellular defense mechanism in irradiated cells soon after exposure to radiation. Thereby, this mechanism protect organism from the effects of low dose ionizing radiation.


Assuntos
Imagem de Perfusão do Miocárdio , Estresse Nitrosativo , Estresse Oxidativo , Renografia por Radioisótopo , Ácido Dimercaptossuccínico Tecnécio Tc 99m , Tecnécio Tc 99m Mertiatida , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
Nucl Med Commun ; 41(10): 1018-1025, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32925827

RESUMO

OBJECTIVE: The F+10 method for diuretic renography (diuretics given 10 min after the radiopharmaceutical) could be a time-conserving method. This method involves a 30-min dynamic acquisition where diuretics are administered only when necessary by the Nuclear Medicine technologist performing the examination. The purpose of this study was to assess the method's performance and to discover the optimal threshold of residual activity for a diuretic administration 7 min into the F+10 renography by reprocessing raw data from prior performed examinations with 20-min acquisitions without diuretics. METHODS: Retrospectively, raw data from 320 original examinations of adult patients performed from 2013 to 2015 were reprocessed into 7-min series and categorized as requiring diuretic or not. The diuretic decisions made by an expert panel were used as a reference. A receiver-operating characteristic curve was drawn to assess the optimal cutoff value for the residual renal activity. Sensitivity, specificity, positive and negative predictive values, as well as the Youden J index were calculated. RESULT: The experts classified 50% (160 examinations) as in need of diuretics. The receiver-operating characteristic curve demonstrated the theoretical optimal cutoff value at 7 min to be 94% of maximum activity (sensitivity 0.93, specificity 0.81, Youden J index 0.73). A clinically acceptable threshold is suggested to be 85% (sensitivity 0.99, specificity 0.59, Youden J index 0.58). CONCLUSION: Tc-mercaptoacetyltriglycine renography with the F+10 method and the threshold 85% for diuretic decision 7 min into the renography is a feasible and acceptable method in clinical practice.


Assuntos
Algoritmos , Diuréticos/administração & dosagem , Renografia por Radioisótopo/métodos , Compostos Radiofarmacêuticos/administração & dosagem , Adulto , Automação , Estudos de Viabilidade , Feminino , Humanos , Masculino , Estudos Retrospectivos , Tecnécio Tc 99m Mertiatida
11.
J Pediatr Urol ; 16(5): 686.e1-686.e6, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32888887

RESUMO

INTRODUCTION: The UTD Classification System risk stratifies postnatal UTD into three groups: low risk (UTD P1), intermediate risk (UTD P2), and high risk (UTD P3). In the original consensus document, a functional scan is not recommended for UTD P1 and is left to the discretion of the clinician for UTD P2 and P3. OBJECTIVE: This study aims to understand which patients with postnatal urinary tract dilation would benefit from a functional study. We investigated how different elements of the UTD classification system predict differential renal function (DRF) and diuretic half-life (T½) on MAG3 scan in infants undergoing evaluation for prenatally detected UTD. STUDY DESIGN: This is a multicenter retrospective chart review of infants 6 months of age or younger evaluated for prenatal UTD, correlating their first MAG3 scan and first postnatal renal ultrasound (RUS). Multivariable logistic regression was used to find UTD elements predictive of DRF < 40% and/or T½ > 20 min. RESULTS: A total of 517 patients met study criteria. Median age at time of RUS and MAG3 renal scan was 48 days (IGR 31-81) and 63 days (IQR 45-98), respectively. DRF < 40% was found in 6% of kidneys with UTD P2 and 35% of kidneys with UTD P3. T½ > 20 min was found in 31% of kidneys with UTD P2 and 79% of kidneys with UTD P3. An abnormal ureter (OR 2.7, 95% CI 1.2-6.0) and parenchymal thinning (OR 16, 95% CI 5.8-41.4) were significant at predicting DRF < 40%. Parenchymal thinning (OR 3.0, 95% CI 1.5-6.1) also predicted T½ > 20 min, as did each cm increase in the anterior-posterior renal pelvic diameter (APRPD) (OR 4.8, 95% CI 3.0-7.7). DISCUSSION: The UTD system discriminates well and correlates with the likelihood of finding adverse features on diuretic renography. Patients in the UTD P3 high-risk category had a significantly higher incidence of decreased differential renal function and delayed drainage than those in UTD P1 and P2. Of the individual components of the UTD Classification system, the presence of parenchymal thinning was the most important factor in predicting both decreased differential renal function and delayed drainage. CONCLUSION: Given the high incidence of poor function and delayed drainage seen in the UTD P3 group, we believe a functional study should be recommended in the evaluation of these patients. Our findings support leaving the performance of a functional study at the discretion of the physician for UTD P2.


Assuntos
Hidronefrose , Renografia por Radioisótopo , Dilatação , Dilatação Patológica/diagnóstico por imagem , Diuréticos , Feminino , Humanos , Lactente , Gravidez , Estudos Retrospectivos
12.
Cir Pediatr ; 33(3): 125-130, 2020 Jul 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32657096

RESUMO

OBJECTIVE: Nowadays, the algorithms for the study of hydronephrosis in children include voiding cystourethrogram (VCUG) and diuretic renogram (DR) in all patients. Both are invasive, distressing, and associated with radiation risk. However, basic renal function tests (bRFTs) are not included. This study was designed to determine whether bRFTs may help avoid VCUG and/or DR in some children. METHODS: Retrospective review of hydronephrosis (≥20 mm renal pelvis) patient records over one year (n = 38) (pyeloureteral stenosis (PUS) n = 12; high-grade vesicoureteral reflux (VUR) n = 8; non-obstructive hydronephrosis (NOH) n = 18. Data from the three protocolized bRFTs (maximum urine osmolality after DDAVP (UOsm), albumin/creatinine ratio (Alb/Cr), and NAG/creatinine ratio (NAG/Cr), together with VCUG and DR, were analyzed. RESULTS: 38 hydronephrosis patients (pyeloureteral stenosis (PUS) n = 12; high grade vesicoureteral reflux (VUR) n = 8; non-obstructive hydronephrosis (NOH) n = 18. UOsm was decreased in 100% of VUR patients, 75% of PUS patients, and 16.7% of NOH patients. Alb/Cr ratio was increased in 62.5% of VUR patients, 8.3% of PUS patients, and 11.1% of NOH patients. NAG/Cr ratio was increased in 42.8% of VUR patients, 25% of PUS patients, and 6.7% of NOH patients. UOsm was decreased in most patients who required surgery (100% of VUR patients and 74% of PUS patients), but only in 11.1% of patients who did not (NOH group). CONCLUSIONS: These results suggest that bRFTs may be useful in delaying or avoiding VCUG in some hydronephrosis cases. UOsm is the most sensitive test. No child with (high grade) VUR had a normal UOsm. VCUG could have been avoided in 43% of our patients -with a normal UOsm- without missing any high grade VUR.


Assuntos
Hidronefrose/diagnóstico , Testes de Função Renal/métodos , Obstrução Ureteral/complicações , Refluxo Vesicoureteral/complicações , Adolescente , Algoritmos , Criança , Pré-Escolar , Feminino , Humanos , Hidronefrose/etiologia , Hidronefrose/terapia , Lactente , Recém-Nascido , Masculino , Renografia por Radioisótopo , Estudos Retrospectivos , Urografia , Adulto Jovem
13.
J Nucl Med Technol ; 48(4): 346-353, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32709669

RESUMO

Our purpose was to develop a fully automatic method to deal with the presence of high levels of noise interfering with quantitative analysis of fast, dynamic mercaptoacetyltriglycine renogram images. Methods: A method based on Legendre polynomials to fit and filter time-activity curves was proposed. The method was applied to a renal database that contains Monte Carlo (MC)-simulated studies and real adult patient data. Clinically relevant parameters such as relative function, time to maximum uptake (Tmax), and half-emptying time (T1/2) were obtained with the proposed method, the 1-2-1 filter (F121) method recommended in the 2018 guidelines of the European Association of Nuclear Medicine, and a state-of-the-art commercial software program (Hermes) currently used in routine nuclear medicine. Results: The root mean squared error between reference time-activity curves and the same curves with Poisson noise added was about 2 times lower for the Legendre method than for F121. The left relative function for MC and patient data was statistically equivalent for Hermes, Legendre, and F121 (P < 0.001). For MC studies, the Legendre technique performed better that the Hermes method regarding the known values of Tmax (P < 0.05), and the T1/2 determination was significantly improved (P < 0.05). For patient data, the Legendre and F121 methods were less influenced by noise in the data than the Hermes method, particularly for T1/2. Conclusion: In dynamic nuclear medicine imaging, Legendre polynomials appear to be a promising, fully automatic noise-removal tool that is routinely applicable, accurate, and robust.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Renografia por Radioisótopo , Tecnécio Tc 99m Mertiatida , Algoritmos , Automação , Padrões de Referência , Razão Sinal-Ruído , Fatores de Tempo
14.
Transplant Proc ; 52(10): 3090-3096, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32605777

RESUMO

BACKGROUND: The clinical utility of 99mTc-mercaptoacetyltriglycine cortical renography for the prediction of graft function in kidney transplant recipients has been unknown. METHODS: We retrospectively reviewed post-transplant cortical renograms in 40 kidney transplant recipients. We analyzed the correlation between T1/2 (elimination half-life) and graft function (measured-to-expected glomerular filtration rate [GFR]) 1 week, and 1, 3, and 6 months post operation compared with whole-kidney renograms. RESULTS: Delayed drainage (T1/2 > 11 minutes) was observed in 22 recipients (55%). T1/2 and postoperative GFR ratio were inversely correlated (1 week: R2 = 0.317, P = .0002; 1 month: R2 = 0.206, P = .003; 3 months: R2 = 0.117, P = .031; 6 months: R2 = 0.161, P = .010). Recipients with delayed drainage had a significantly lower GFR ratio than those with normal drainage 1 week (median, 0.93 vs 1.32; P = .001), 1 month (median, 1.65 vs 2.23; P = .0010), 3 months (median, 1.55 vs 2.17; P = .041), and 6 months (median, 1.67 vs 2.34; P = .018) post operation, respectively. Whole-kidney renograms failed to discriminate recipients with lower GFR ratio at 1, 3, and 6 months. CONCLUSIONS: T1/2 in post-transplant cortical renography was inversely correlated with early graft function and may predict early post-transplant graft function.


Assuntos
Nefropatias/diagnóstico por imagem , Transplante de Rim , Complicações Pós-Operatórias/diagnóstico por imagem , Renografia por Radioisótopo/métodos , Adulto , Idoso , Feminino , Humanos , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Tecnécio Tc 99m Mertiatida , Adulto Jovem
15.
Cir. pediátr ; 33(3): 124-130, jul. 2020. tab
Artigo em Espanhol | IBECS | ID: ibc-193554

RESUMO

OBJETIVO: Actualmente, los algoritmos para estudiar hidronefrosis en niños incluyen realizar cistografía miccional (CUMS) y renograma diurético (RD) a todos. Ambos son invasivos, molestos y con riesgo de radiación. Contrariamente, las pruebas básicas de función renal (PFRb) no están incluidas. Este estudio se realizó para saber si las PFRb pueden ayudarnos a evitar alguna CUMS y/o RD. MÉTODOS: Análisis retrospectivo de todas las historias de niños con hidronefrosis (pelvis renal ≥ 20 mm) atendidos durante un año (n = 38), [estenosis pieloureteral (EPU) n = 12; reflujo vesicoureteral (RVU) de alto grado n = 8; hidronefrosis no obstructiva (HNO) n = 18]. Analizamos las tres PFRb protocolizadas [osmolalidad urinaria máxima tras DDAVP (UOsm), albúmina/creatinina (Alb/Cr) y NAG/creatinina (NAG/Cr)], junto con CUMS y RD. RESULTADOS: UOsm estaba disminuida en 100% RVU, 75% EPU, 16,7% HNO. Alb/Cr estaba aumentado en 62,5% RVU, 8,3% EPU, 11,1% HNO. NAG/Cr estaba aumentado en 42,8% RVU, 25% EPU, 6,7% HNO. En relación a la necesidad de cirugía, UOsm estaba disminuida en la mayoría de pacientes intervenidos (100% con RVU y 74% con EPU), mientras solo en el 11% de pacientes sin cirugía (HNO). CONCLUSIÓN: Estos resultados sugieren que las PFRb pueden ser útiles para retrasar o evitar CUMS en algunos niños con hidronefrosis. La UOsm es la PFRb más sensible. Ningún niño con RVU (de alto grado) mostró una UOsm normal. Se podrían haber evitado CUMS en el 43% de nuestros pacientes, con UOsm normal, sin haber perdido ningún diagnóstico de VUR (de alto grado)


OBJECTIVE: Nowadays, the algorithms for the study of hydronephrosis in children include voiding cystourethrogram (VCUG) and diuretic renogram (DR) in all patients. Both are invasive, distressing, and associated with radiation risk. However, basic renal function tests (bRFTs) are not included. This study was designed to determine whether bRFTs may help avoid VCUG and/or DR in some children. METHODS: Retrospective review of hydronephrosis (≥ 20 mm renal pelvis) patient records over one year (n = 38) (pyeloureteral stenosis (PUS) n = 12; high-grade vesicoureteral reflux (VUR) n = 8; non-obstructive hydronephrosis (NOH) n = 18. Data from the three protocolized bRFTs (maximum urine osmolality after DDAVP (UOsm), albumin/creatinine ratio (Alb/Cr), and NAG/creatinine ratio (NAG/Cr), together with VCUG and DR, were analyzed. RESULTS: 38 hydronephrosis patients (pyeloureteral stenosis (PUS) n = 12; high grade vesicoureteral reflux (VUR) n = 8; non-obstructive hydronephrosis (NOH) n = 18. UOsm was decreased in 100% of VUR patients, 75% of PUS patients, and 16.7% of NOH patients. Alb/Cr ratio was increased in 62.5% of VUR patients, 8.3% of PUS patients, and 11.1% of NOH patients. NAG/Cr ratio was increased in 42.8% of VUR patients, 25% of PUS patients, and 6.7% of NOH patients. UOsm was decreased in most patients who required surgery (100% of VUR patients and 74% of PUS patients), but only in 11.1% of patients who did not (NOH group). CONCLUSIONS: These results suggest that bRFTs may be useful in delaying or avoiding VCUG in some hydronephrosis cases. UOsm is the most sensitive test. No child with (high grade) VUR had a normal UOsm. VCUG could have been avoided in 43% of our patients –with a normal UOsm-without missing any high grade VUR


Assuntos
Humanos , Masculino , Feminino , Lactente , Hidronefrose/diagnóstico por imagem , Hidronefrose/cirurgia , Algoritmos , Cistografia , Renografia por Radioisótopo , Estudos Retrospectivos , Pelve Renal/diagnóstico por imagem , Pelve Renal/patologia , Albuminúria/diagnóstico , Refluxo Vesicoureteral/diagnóstico , Razão de Chances , Técnicas de Laboratório Clínico
16.
Scand J Clin Lab Invest ; 80(5): 408-411, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32362172

RESUMO

The issue of whether 99mTc-DTPA can replace 51Cr-EDTA for measurement of plasma clearance as a surrogate for glomerular filtration rate (GFR) is of great relevance to daily clinical practice. Prompted by the shortage of 51Cr-EDTA we conducted a head-to-head comparison in patients attending our department for GFR determination. The two tracers (3.7 MBq of 51Cr-EDTA and 8 MBq of 99mTc-DTPA) were administered intravenously immediately after each other, and the standard number of blood samples were drawn. Fifty-four patients were enrolled. In 51 of these, single-sample measurement was performed with the following results: GFREDTA was 84.6 ± 23.3 mL/min, GFRDTPA was 84.2 ± 24.7 mL/min. The mean difference was 0.4 ± 2.8 mL/min, p = 0.32, and results based on the two tracers were highly correlated (r = 0.995). GFRDTPA exceeded GFREDTA at high GFR values (difference < 0 at GFREDTA >91.4 mL/min) and vice versa (difference > 0 at GFREDTA < 91.4 mL/min). However, differences fell within few GFR units that most often will have no clinical consequence. We therefore conclude that 99mTc-DTPA can replace 51Cr-EDTA for single-sample determination of GFR in a clinical setting.


Assuntos
Ácido Edético/farmacocinética , Taxa de Filtração Glomerular/fisiologia , Renografia por Radioisótopo/métodos , Compostos Radiofarmacêuticos/farmacocinética , Pentetato de Tecnécio Tc 99m/farmacocinética , Administração Intravenosa , Idoso , Radioisótopos de Cromo , Feminino , Humanos , Rim/fisiologia , Masculino , Pessoa de Meia-Idade , Renografia por Radioisótopo/normas
17.
Ann Nucl Med ; 34(5): 349-357, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32166712

RESUMO

OBJECTIVE: Gamma camera-based measurement of glomerular filtration rate (GFR) with 99mTc-diethylenetriaminepentaacetic acid (DTPA) is an established non-invasive measurement of split renal function; however, it is not as accurate as the plasma sample method. Therefore, study into improving the accuracy of such method is clinically relevant. The aim of this study was to elucidate the feasibility of gamma camera-based GFR measurement using renal depth evaluated by lateral scan of 99mTc-DTPA renography and comparing the results with those of GFR using renal depth measured by CT, and three representative formulas. METHODS: The study population comprised 38 patients (median, 69 years; male 28, female 10; median estimated GFR, 67.4 ml/min) with renourinary disorders. Scintigraphy was performed after intravenous injection of 370 MBq 99mTc-DTPA by dynamic data acquisition for 20 min, followed by a bilateral static scan of the abdomen for 3 min. All patients underwent computed tomography (CT) within 2 months from renography. GFR was calculated by renography using renal depth determined in five ways; lateral scan of 99mTc-DTPA, CT, and three formulas previously created with using weight, height and age. GFRs were compared with estimated GFR (eGFR). The depth of both kidneys measured as described above was compared and evaluated the laterality of the renal depth. RESULTS: The median values of GFR calculated with renal depth determined by 99mTc-DTPA renography, CT, and the three formulas were 87.3, 83.9, 67.8, 68.3, and 71.5 ml/min, respectively. All of them correlated significantly with eGFR (r = 0.734, r = 0.687, r = 0.728, r = 0.726, and r = 0.686, respectively), however, no significant difference was observed among five correlation coefficients. Bland-Altman plot revealed that eGFR had error and fixed bias when compared with GFRs calculated using renal depth determined by renography, CT, and Taylor's formula. The depth of both kidneys measured by 99mTc-DTPA renography was equivalent to that measured by CT, however, those measured by the three formulas were significantly smaller than that measured by 99mTc-DTPA renography. The depth of the right kidney was larger than that of the left kidney using all three formulas in all patients. However, CT detected only 66% of patients to have a deeper right kidney than left kidney. CONCLUSION: Lateral scanning is a feasible procedure to measure renal depth for accurate and reasonable split GFR measurements using 99mTc-DTPA renography.


Assuntos
Câmaras gama , Taxa de Filtração Glomerular , Processamento de Imagem Assistida por Computador , Renografia por Radioisótopo/instrumentação , Pentetato de Tecnécio Tc 99m , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Diabetes Res Clin Pract ; 161: 108079, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32057963

RESUMO

AIMS: To investigate the agreement of glomerular filtration rate (GFR) determination between 51Cr-ethylenediaminetetraacetic acid (51Cr-EDTA) plasma clearance (GFREDTA) and 99mTc-diethylenetriaminepentaacetic acid (99mTc-DTPA) plasma clearance (GFRDTPA), the Gates 99mTc-DTPA renographic method (GFRGates) and the serum creatinine Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI, GFRSCr) in patients with type 2 diabetes mellitus (T2DM). METHODS: Ninety-nine T2DM patients underwent GFR determinations simultaneously with 51Cr-EDTA and 99mTc-DTPA (using the slope-intercept technique and the Brochner-Mortensen correction) and also with GFRGates and GFRSCr. RESULTS: In the comparison between GFREDTA versus GFRDTPA, GFRGates and GFRSCr, the Bland-Altman statistic provided 0.0 ± 13.2, 17.4* ± 28.8 and -5.9* ± 30.1 (*p < 0.001 for the difference from 0). Lin's concordance correlation coefficient showed substantial (0.976), poor (0.737) and poor (0.872) agreement, respectively. The proportion of the index results within the 30% and 10% of GFREDTA measurements were 95% and 74% for GFRDTPA, 53% and 19% for GFRGates, and 83% and 26% for GFRSCr, respectively. CONCLUSION: In T2DM patients, a clinically acceptable agreement is demonstrated between 51Cr-EDTA and 99mTc-DTPA plasma clearance for GFR measurements, suggesting conditional interchangeability between those compounds. Both the CKD-EPI prediction equation and the Gates' renographic method cannot assess GFR reliably, the latter appearing less unfailing than the former.


Assuntos
Creatinina/metabolismo , Diabetes Mellitus Tipo 2/sangue , Taxa de Filtração Glomerular/fisiologia , Insuficiência Renal Crônica/sangue , Pentetato de Tecnécio Tc 99m/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Renografia por Radioisótopo , Insuficiência Renal Crônica/diagnóstico , Adulto Jovem
19.
J Pediatr Urol ; 16(2): 189.e1-189.e7, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31953013

RESUMO

INTRODUCTION: The association of high-grade vesico-ureteral reflux (VUR) with renal dysplasia and/or scarring is well-established, and the combination of these factors has been shown to decrease the likelihood of VUR resolution. Other VUR parameters have similarly been shown to be associated with VUR non-resolution, including VUR grade and timing at cystography, associated urinary tract anatomical abnormalities, and bladder dysfunction. OBJECTIVE: To establish independent risk factors that can predict symptomatic persistence of VUR. DESIGN: This was a single-centre study (2011-2017) including consecutive prospectively collected patients with primary VUR on voiding cystourethrogram (VCUG). Patients with dilating VUR also underwent renography (dimercaptosuccinic acid [DMSA] or 99m-technetium mercaptoacetyltriglycine [99mTc-MAG3]). All patients were initially managed medically with antibiotic prophylaxis. Primary outcome was febrile culture-positive breakthrough urinary tract infection (BT-UTI). Demographic parameters, as well as VUR grade, VUR timing at cystography, presence of ureteral anomaly, VUR index (VURx), and differential renal function (DRF) or scarring were analysed to determine independent predictors. RESULTS: A total of 61 patients (41 male, of whom 7 circumcised at presentation) were studied. VUR was diagnosed following investigation of prenatal hydronephrosis in 37 patients (62%) and following a febrile UTI in 22 (37%). Median [range] follow-up period was 38 [12-84] months. Data from a total of 77 refluxing renal units (RUs) were used for analysis. Analysis of VCUG data demonstrated that high VURx might be a potential significant predictor of breakthrough UTI (RR: 1.7, 95% CI: 1.1-2.7, p < 0.05 vs low VURx) but this was not the case for individual VURx components. Renography data showed increased risk of breakthrough UTI in patients with renal scarring (relative risk (RR): 5.1, 95% confidence interval (CI: 2.0-10.7, p < 0.0001 vs no renal scarring), but not in patients with reduced DRF. Multivariate regression analysis revealed that renal scarring was the only significant risk factor for breakthrough UTI. VUR patients with renal scarring were three times more likely to develop breakthrough UTI (odds ratio (OR): 3.3, 95% CI: 1.4-7.4, p < 0.01). DISCUSSION: Multiple factors have been shown to be significant predictors of radiological VUR resolution. Univariate analysis of these factors suggests that only scarring on DMSA and VURx are significant predictors of symptomatic non-resolution. On multivariate analysis, scarring on DMSA was the only significant predictive variable. This information will be useful in targeting investigation and treatment in susceptible patients and when counselling families. CONCLUSION: Renal scarring is the most significant risk factor for breakthrough UTI in primary VUR patients and could be used to determine those at risk of symptomatic VUR persistence.


Assuntos
Infecções Urinárias , Refluxo Vesicoureteral , Cicatriz/diagnóstico por imagem , Cicatriz/etiologia , Cistografia , Humanos , Lactente , Masculino , Renografia por Radioisótopo , Estudos Retrospectivos , Infecções Urinárias/complicações , Infecções Urinárias/epidemiologia , Refluxo Vesicoureteral/complicações , Refluxo Vesicoureteral/diagnóstico por imagem
20.
Nucl Med Commun ; 41(2): 96-103, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31860527

RESUMO

OBJECTIVE: The aim of this study was to estimate interobserver reproducibility of Tc-99m mercaptoacetyltriglycine renography in children and adults by assessing the parameters of the International Atomic Energy Agency (IAEA) software for the analysis of dynamic renal studies. METHODS: The renograms of 65 children and 65 adults covered a wide age range, different quality of drainage, overall function and differential renal function (DRF). Three observers were processing parameters of the IAEA software. Normalized residual activity at 20 min (NORA20), NORA on the postmicturition acquisition (NORApm), PM to maximum renal count ratio (PM/max), output efficiency at 20 min (OE20), OE 20 min after diuretic stimulation (OEF + 20), whole kidney mean transit time (MTT) and DRF by integral and Rutland-Patlak were calculated by observers. RESULTS: The overall agreement between three observers was almost perfect [the average intraclass correlation coefficient (ICC) above 0.99] in children and adults, with no significant difference between the parameters of renal drainage, transit and DRF. ICCs for all parameters were higher than 0.980 in children under 12 months, even slightly greater for PM/max and OEF+20. In children with poor/incomplete drainage and DRF below 40%, ICCs were above 0.98. In the subgroup of adults with impaired overall tubular extraction rate, level of reproducibility was almost perfect. Slightly lower but still insignificant values of ICC were presented in adults with poor/incomplete drainage. CONCLUSION: Our results indicate an excellent interobserver reproducibility for all quantitative parameters of IAEA software in both pediatric and adult patients.


Assuntos
Processamento de Imagem Assistida por Computador , Agências Internacionais , Renografia por Radioisótopo , Software , Tecnécio Tc 99m Mertiatida , Obstrução Ureteral/diagnóstico por imagem , Obstrução Ureteral/fisiopatologia , Adulto , Criança , Drenagem , Feminino , Humanos , Lactente , Testes de Função Renal , Masculino , Variações Dependentes do Observador
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