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Non-contrast CT of the kidneys shows a hyperdense small stone (2mm) at the left middle calyx, which was adequately visualised on SDCT (b) better than on LDCT (a).
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Objective
To evaluate the detectability, size, location and density of urinary stones with unenhanced computed tomography (CT), using the half-radiation (low) dose (LDCT) technique, compared with the standard-dose CT (SDCT), in obese patients.
Patients and methods
The study included 50 patients with a body mass index of >30 kg/m2 and bilateral ren...
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... A study by Uppot et al. [41] in the United States has reported a 94% accuracy in detecting ureterolithiasis in their sample of 50 patients with obesity. Recently, a study by Abou El-Ghar et al. [42] conducted in Egypt assessed the efficacy of low-dose CT protocol in detecting nephrolithiasis in 50 patients with BMI >30 kg/m 2 . They have reported that low-dose CT protocols are as accurate as the standard-dose CT in detecting calculi, irrespective of size and location, while avoiding patient exposure to high doses of radiation, even in patient populations with obesity. ...
Background. Noncontrast computed tomography (CT) scan of the kidneys, ureter and bladder is the standard investigative modality for diagnosing and following up patients with urolithiasis. With each scan, a patient receives radiation of 18–34 mGy. Dose considerations become pertinent because of a 10% lifetime incidence rate and higher than 50% risk of recurrence, necessitating repeated imaging in the lifetime of a stone former. Hence, this study aimed to assess the sensitivity of “reduced-radiation” CT imaging by altering scan settings to lower than the “standard” norms.
Materials and methods. Altogether, 222 patients (255 “kidney-ureter” stone-bearing units or “renal units”) with urolithiasis and patients undergoing CT for other reasons with incidental findings of renal/ureteric calculi between 2017 and 2019 were included. All patients were subjected to 3 sequential scans at tube current settings of 250 mA (CT-N/Standard), 100 mA (CT-100), and 50 mA (CT-50) at a constant voltage of 120 kV. Their clinicodemographic and radiological findings were recorded and assessed for significance.
Results. Of the 255 renal units, 117 were between 30 and 44 years of age, 75% were men. Of the 255 patients, 178 (70.1%) reported a first stone episode and 77 had recurrence. Lower ureteric calculi were predominant (40.4%). All calculi were identified on CT-N; CT-100 failed to detect calculi in 1 patient, and CT-50 failed in 3 patients, where all calculi were
... In the case of 3-dimensional segmentation, the concentrations of left overs from blood urea nitrogen and serum creatinine will not cross the typical reference level until the kidney fails to function more than 75% [42]. The level of blood urea nitrogen is not clearly defined because of the consumption of protein and blood flow in the kidney [1]. The functioning of kidney tests can be achieved more accurately by evaluating the glomerular filtration rate (GFR) that is used to calculate how efficiently the blood is purified and toxins are eliminated from the kidneys. ...
... In the second stage, the mean is calculated for all minimum intensity pixels as shown in the flow chart to improve the intensity of each pixel of the image. The enhanced image which is got from Eqs. (1) to (5) is applied for smoothening technique and the mean curvature of the image (M) is calculated by ...
The current study of kidney stones made by the National Health and Nutrition Examination Survey (NHANES) describes that over the last eighty years the number of stones present in the kidney is significantly enhanced by approximately 70% (2015). According to Malaysian Dialysis and information of Transplant Registry, there is a constant increase in the number of patients who are registering newly, and the increase from 2002 to 2010 is 2375, 5153 from 2011 to 2014, and from 2015 to 2016 it is 5201. A standardized data system in the United States (2008–2009). In the United States Renal Data System which captures, evaluates, and generates reports that are based on end-stage renal disease and diseases of the kidney. Some of the pathological changes of the kidney are the formation of stones, variations in the state of its position, and inflammation of the kidney. It is very essential to recognize the precise and correct position of stone in the kidney for interventional procedures. For further analysis, the ultrasound images are considered as a challenging task because of its significantly low intensity and additive sound. Therefore, to eliminate the additive noise present in the image, preprocessing of the US is performed. The preprocessed US image by using Plain Intensity Filter is fed to feature extraction technique extracted by deep learning-based advanced Symlets, Daubechies, and Biorthogonal wavelet sub-bands filters to extract kidney image and stones. These features are subjected to segmentation using a Novel Deep and Machine learning Reaction–Diffusion (RD) level set segmentation (LSS). It employs a two-step division process to recursively solve the equation of RD-LSS such as reaction and diffusion. The reaction is to minimize the numerical errors and the diffusion is employed to normalize the set function level for better stability. The RD-LSS also eliminates the anti-leakages on image boundary without requiring any expensive re-initialization. Wavelet sub-bands are used to obtain energy and mean levels and the average levels provide a sign of the absence or existence of stones. These levels of energy are accomplished through Machine learning algorithms with the help of Back Propagation, Multilayer Perceptron, and Support Vector Machine ANN (Verma et al. in Pattern Recognit Image Anal 27:574–580, 35). After successfully training by Machine learning algorithms, the proposed system can identify the single and multiple stones with an accuracy of 98.9% in terms of detection of stone in US images compared with the existing detection techniques that give 92.1% accuracy.
... In a study by Abou El-Ghar et al. [24] they were used variable tube current to obtain half of the radiation dose from the automated dose generated at SDCT, and they modified the dose according to body weight, and this yielded an acceptable image quality that allowed a high diagnostic accuracy (100%). ...
... Other investigators used modulated changeable low dose of tube current according to gender and weight of the patient, Abou El-Ghar et al. [24] used variable tube current to obtain half of the radiation dose from the automated dose generated at SDCT, they modified the dose according to body weight, and this yielded an acceptable image quality that allowed a high diagnostic accuracy (100%). ...
IntroductIon Computed tomography (CT) is recommended by several authors at present as the initial diagnostic imaging technique in patients with suspected renal colic because of its high sensitivity and specificity for the detection of stone. [1-4] The initial use of CT reveals the presence of a stone, its size and location, [5] these give us a useful information for selecting the most appropriate therapeutic approach. [6] However, because renal colic frequently affects young adults, with a recurrence rate of about 50%, [7] the systematic use of CT at a patient's admission raises an ethical concern about the dose of radiation administered. [8,9] Many authors have reported that low-dose CT (LDCT) protocols, the term LDCT scan refers to radiation dose of CT scans where compared to a "normal" or "standard" dose scan, the image quality has been modified to reduce the exposure dose while preserving the diagnostic performance, [10] low-dose CT is suitable for urolithiasis and renal colic because of the good spontaneous contrast between most urinary stones that are spontaneously hyper attenuating (between 200 and 2800 HU) [11] and the soft tissues that surround them, thus even if the dose reduction is substantial, the naturally high contrast between urinary stones and the surrounding soft tissues prevents too much deterioration of the contrast-to-noise ratio while preserving good diagnostic performance. [12] Background: Computed tomography (CT) (standard and low-dose CT [LDCT] scan) has become the reference technique in medical imaging for urinary calculi, to diagnose, plan treatment, and explore differential diagnosis of renal colic. Objective: This study was done to compare the low-dose nonenhanced CT scan with standard dose CT scan in the detection of urolithiasis. Materials and Methods: Cross-sectional study conducted from 2017 to 2018 in Al-Hilla teaching general hospital on 60 patients undergone unenhanced (native) spectral detector CT (SDCT) and LDCT, the patients were scanned by Siemens CT system, 64 slice using automated tube current modulation, all CT scan were performed without oral or intravenous contrast. Results: This study showed that 93 stones detected by SDCT scan and 89 stones detected by LDCT scan, mean age of patients 44.2 ± 7.3 and mean of body mass index 26.3 ± 3.1, male constitute 56.6% (34) and female 43.4% (26). In 46.6% of patients had stone in the left side and 53.4% show stone in right side, most of patients presented solitary stone which appear 73.4%, 11.6% of patients had double stone, 5% had triple stone, 6.6% had four stones, and 3.45% had 5 or more stone at investigation, 10.8% of stones lie in ureter, 7.6% of stones in renal pelvis, 13.9% in upper calyx, 28% in lower calyx, and 39.7% lie in middle calyx, according to size of stones 11.9% of stones had size <3 mm, 35.4% of stones range 3-5 mm, 34.5% size range 6-10 mm, 12.9% 11-15 mm in size, 3.25 of stones had size range 16-20 mm and only 2.1% of stone had size >20 mm. In standard CT scan, the current mean was 283.2 while in LDCT scan the mean was 126.1 mA, sensitivity is (93%) and specificity (100%) of LDCT in reference SDCT. Conclusion: LDCT scans provide effective methods of identifying and evaluating urinary tract stones, high diagnostic accuracy, sensitivity, and specificity are maintained despite significant radiation dose reduction compared to standard dose CT.
... 8,[10][11][12] Conventional NCCT and Low dose NCCT has been compared in the medical literature. [12][13][14] In a study by Alsyouf and colleagues, low dose CT at variable mAs resulted in similar attenuation values (as a surrogate for stone composition) compared with Conventional-dose CT with only a slight increase in variability. 15 A study by Sohn and associates supported this observation, demonstrating no significant difference in measurement of stone size, attenuation, or SSD between low dose and conventional-dose CT with a marked reduction in radiation dose of 73% (from 23 to 6 mSv). ...
Background: The incidence, prevalence and recurrence of urolithiasis are very high; especially in the north-western part of India. Ultrasonography has decreased sensitivity and specificity as compared with NCCT for detection of both renal and ureteral calculi. Drawbacks of NCCT in terms of radiation exposure, cost and repeatability can be overcome by Low dose NCCT protocols. Low dose NCCT can be an investigation with high diagnostic accuracy, less radiation hazards and financial acceptability. Aim of this study was to evaluate use of Low dose CT-KUB over ultrasound (US) for diagnosis of urolithiasis, in Indian scenario.Methods: This is a prospective study, at Tertiary Care Hospital. Patients with acute flank pain, who underwent both US and Low dose NCCT within an interval of 24 hours, at Tertiary Care Hospital. Helical CT scanner (Phillips 128 slice medical systems) with exposure factors setting of KVp 120 and mAs 70 was used.Results: A total of 136 Patients with mean age of 33.01 years (range 19-62 years, SD 10.93), were examined with 82(60.29%) males and 54(39.7%) females, average BMI was 25.07(range 17.2 to 35.02). Low Dose NCCT has a sensitivity of 95% (CI of 89.43-98.14%) and specificity of 87.50% (95% CI of 61.65-98.45%) in the diagnosis of urolithiasis. Mean effective dose of radiation administered in low dose CT-KUB was 1.8-2.2 mSv.Conclusions: In view of information, reliability, repeatability, radiation exposure and cost acceptability; unenhanced Low dose CT-KUB region should be the preferred investigation for the management of urolithiasis, in the scenario of a developing country.
... в исследовании, посвященном оценке возможностей МСКТ протоколов с низкой лучевой нагрузкой и итеративной реконструкцией у пациентов с избыточным весом при диагностике почечной колики [16]. Также об отсутствии затруднений в диагностике почечной колики у пациентов с ожирением сообщают El-Ghar и соавт., применявшие МСКТ протокол с низкой силой тока [17]. ...
Purpose. The aim of this study was to evaluate the possibilities of low-tube voltage MDCT in visualization of liver and pancreatic tumors. Materials and methods. 75 patients were enrolled in study and divided into 3 groups. All studies were performed with intravenous administration of a contrast media. Three scanning protocols were used, differing by the voltage on the X-ray tube-standard 120 kV-90 ml CM, the modified 100 kV-90 ml CM and low-iodine load protocol-100 kV-65 ml CM. The data - A noise, a circumference of abdominal cavity, a relation "contrastnoise", data of CT-numbers of organs were evaluated. The tomograms were reconstructed using standard and iterative reconstruction algorithms. A qualitative assessment of the images was carried out according to 2 parameters-the evaluation of the whole image and the visualization of tumor on a 3-point scale. Results and discussion. Radiation exposure decreased by 32,2% and 36,7%, using the modified protocols "100 kV-90 CM" and "100 kV-65 CM", respectively. The noise level did not differ with the use of standard reconstruction, but it decreased markedly using iterative reconstruction. The contrast-to-noise ratio turned out to be higher in the "100 kV-90 CM" group and consistently increased with increasing levels of iterative reconstruction. Evaluations of the visualization of tumors were significantly higher in the "100 kV-90 CM" group. Using low-iodine load protocol "100 kV-65 CM" demonstrated results similar to "120 kV-90 CM" protocol. Conclusions. The use of low-tube voltage MDCT improves visualization of the liver and pancreas hypo-and hypervascular tumors, in addition, it allows to reduce the radiation exposure. © 2018 Russian Electronic Journal of Radiology. All rights reserved.
... в исследовании, посвященном оценке возможностей низкодозовых протоколов и итеративной реконструкции у пациентов с избыточной массой тела при диагностике почечной колики [11]. Также об отсутствии затруднений в диагностике почечной колики у пациентов с ожирением сообщают M. E. El-Ghar и соавт., применявшие протокол с пониженной силой тока [12]. ...
Aims : to evaluate the possibilities of low-dose MDCT protocols in visualization of liver and pancreatic tumors. Materials and methods . 40 patients were enrolled in study and divided into 2 groups. Two scanning protocols were used, differing by the voltage on the X-ray tube-standard 120 kV, and the modified 100 kV. All studies were performed with intravenous administration of a contrast agent. The data – noise, a circumference of abdominal cavity, a relation “contrast-noise”, data of contrast strengthening of organs were evaluated. The tomograms were reconstructed using standard and iterative reconstruction algorithms. A qualitative assessment of the images was carried out according to 2 parameters – the evaluation of the whole image and the visualization of tumor on a 3-point scale. Results . Radiation exposure decreased by 31.5% using the modified protocol. The noise level did not differ with the use of standard reconstruction, but it decreased markedly using iterative reconstruction. The contrast-to-noise ratio turned out to be higher in the “100 kV” group and consistently increased with increasing levels of iterative reconstruction. Evaluations of the visualization of tumors were significantly higher in the “100 kV” group. Conclusion . The use of low-dose protocols is justified, it allows to seriously reduce the radiation exposure, improving visualization of the liver and pancreas tumors (primarily hypervascular). Application of iterative reconstruction algorithms allows achieving significant improvement in image quality and noise reduction.
... Accuracy of the results was found to be correct up to 97% [5]. Norihiro Koizumi has proposed high intensity focused ultrasound (HIFU) technique for terminating tumours and stones [6,7]. Viswanath and Gunasundari propose content descriptive multiple stones detection using level set segmentation, wavelets processing for identification of kidney stone, and artificial neural network (ANN) for classification. ...
... Templates based technique was proposed by Emmanouil Skounakis for 3D detection of kidneys and their pathology in real time. Its accuracy was found to be 97.2% and abnormalities in kidneys had an accuracy of 96.1% [7]. Gabor function is used for achievement of optimal sharpening and smoothening of 2D image in both time and frequency resolutions [14]. ...
Ultrasound imaging is one of the available imaging techniques used for diagnosis of kidney abnormalities, which may be like change in shape and position and swelling of limb; there are also other Kidney abnormalities such as formation of stones, cysts, blockage of urine, congenital anomalies, and cancerous cells. During surgical processes it is vital to recognize the true and precise location of kidney stone. The detection of kidney stones using ultrasound imaging is a highly challenging task as they are of low contrast and contain speckle noise. This challenge is overcome by employing suitable image processing techniques. The ultrasound image is first preprocessed to get rid of speckle noise using the image restoration process. The restored image is smoothened using Gabor filter and the subsequent image is enhanced by histogram equalization. The preprocessed image is achieved with level set segmentation to detect the stone region. Segmentation process is employed twice for getting better results; first to segment kidney portion and then to segment the stone portion, respectively. In this work, the level set segmentation uses two terms, namely, momentum and resilient propagation (
R
prop
) to detect the stone portion. After segmentation, the extracted region of the kidney stone is given to Symlets, Biorthogonal (bio3.7, bio3.9, and bio4.4), and Daubechies lifting scheme wavelet subbands to extract energy levels. These energy levels provide evidence about presence of stone, by comparing them with that of the normal energy levels. They are trained by multilayer perceptron (MLP) and back propagation (BP) ANN to classify and its type of stone with an accuracy of 98.8%. The prosed work is designed and real time is implemented on both Filed Programmable Gate Array Vertex-2Pro FPGA using Xilinx System Generator (XSG) Verilog and Matlab 2012a.
... Accuracy of the results was found to be correct up to 97% [5]. Norihiro Koizumi has proposed high intensity focused ultrasound (HIFU) technique for terminating tumours and stones [6,7]. Viswanath and Gunasundari propose content descriptive multiple stones detection using level set segmentation, wavelets processing for identification of kidney stone, and artificial neural network (ANN) for classification. ...
... Templates based technique was proposed by Emmanouil Skounakis for 3D detection of kidneys and their pathology in real time. Its accuracy was found to be 97.2% and abnormalities in kidneys had an accuracy of 96.1% [7]. Gabor function is used for achievement of optimal sharpening and smoothening of 2D image in both time and frequency resolutions [14]. ...
This paper gives an overview of the mathematical aspects of artificial neural networks theory presenting it broadly as a problem of constructing dynamical systems with given properties. It is also shown how computer simulations on a mathematical model have suggested a theory of dreams to the two biologists F. Crick and G. Mitchison.
Imaging plays an important role in the evaluation and treatment of urology patients, especially in the field of endourology. However, the total ionizing radiation exposure to US citizens had almost doubled over the previous two decades according to a National Council on Radiation Protection and Measurements (NCRP) report, which attributed this to increased exposure from computed tomography scans, image‐guided fluoroscopic procedures, and nuclear medicine studies. Therefore, different international organizations and institutions, such the International Atomic Energy Agency, the NCRP, the International Commission on Radiological Protection, and the US Food and Drug Administration have made several recommendations for judicious use of ionizing radiation. All emphasized the principles of justification of imaging studies and optimization of the imaging process in a way that gives the necessary information with the lowest dose of radiation. In addition, the “as low as reasonably achievable” (or ALARA) principles of minimizing time, maximizing distance, and always wearing appropriate shields have been developed. In addition to elucidating ALARA principles, this chapter will explain the basic anatomy of the X‐ray tube, and the generation of X‐rays. Furthermore, it will go through potential hazards of ionizing radiation. Finally, the role of virtual reality simulators in minimizing radiation exposure during fluoroscopic‐guided percutaneous renal access will be explored. By the end of this chapter readers will have developed strategies in lowering radiation exposure during diagnosis, treatment, and follow‐up of their patients requiring endourologic procedures.
Kidney stone detection is one of the sensitive topic now-a-days. There are various problem associates with this topic like low resolution of image, similarity of kidney stone and prediction of stone in the new image of kidney. Ultrasound images have low contrast and are difficult to detect and extract the region of interest. Therefore, the image has to go through the preprocessing which normally contains image enhancement. The aim behind this operation is to find the out the best quality, so that the identification becomes easier. Medical imaging is one of the fundamental imaging, because they are used in more sensitive field which is a medical field and it must be accurate. In this paper, we first proceed for the enhancement of the image with the help of median filter, Gaussian filter and un-sharp masking. After that we use morphological operations like erosion and dilation and then entropy based segmentation is used to find the region of interest and finally we use KNN and SVM classification techniques for the analysis of kidney stone images.
