Search Results (300)

Background/Objectives: Ultrasound imaging is widely employed to assess kidney health and diagnose renal diseases. Accurate segmentation of renal structures in ultrasound images plays a critical role in the diagnosis and treatment of related kidney diseases. However, challenges such as speckle noise and low contrast still hinder precise segmentation. Methods: In this work, we propose an encoder–decoder architecture, named MAT-UNet, which incorporates two distinct attention mechanisms to enhance segmentation accuracy. Specifically, the multi-convolution pixel-wise attention module utilizes the pixel-wise attention to enable the network to focus more effectively on important features at each stage. Furthermore, the triple-branch multi-head self-attention mechanism leverages the different convolution layers to obtain diverse receptive fields, capture global contextual information, compensate for the local receptive field limitations of convolution operations, and boost the segmentation performance. We evaluate the segmentation performance of the proposed MAT-UNet using the Open Kidney US Data Set (OKUD). Results: For renal capsule segmentation, MAT-UNet achieves a Dice Similarity Coefficient (DSC) of 93.83%, a 95% Hausdorff Distance (HD95) of 32.02 mm, an Average Surface Distance (ASD) of 9.80 mm, and an Intersection over Union (IOU) of 88.74%. Additionally, MAT-UNet achieves a DSC of 84.34%, HD95 of 35.79 mm, ASD of 11.17 mm, and IOU of 74.26% for central echo complex segmentation; a DSC of 66.34%, HD95 of 82.54 mm, ASD of 19.52 mm, and IOU of 51.78% for renal medulla segmentation; and a DSC of 58.93%, HD95 of 107.02 mm, ASD of 21.69 mm, and IOU of 43.61% for renal cortex segmentation. Conclusions: The experimental results demonstrate that our proposed MAT-UNet achieves superior performance in multiple renal structure segmentation in ultrasound images. Full article

An adult female bottlenose dolphin (Tursiops truncatus) housed at a public oceanarium presented with acute anorexia and lethargy. A blood analysis demonstrated mild leukocytosis, marked azotemia, hyperkalemia, and hyperphosphatemia suggestive of acute kidney injury or renal insufficiency. Ultrasound examination of the dolphin revealed ascites, pleural effusion, bilateral nephrolithiasis, mild hydronephrosis, and bilateral hydroureter consistent with bilateral post-renal obstruction. Initial treatment consisted of antibiotics, oral fluids, and anti-inflammatory treatment. Further imaging diagnosed bilateral obstructing ureteroliths at both ureteral orifice junctions of the urinary bladder. The dolphin’s azotemia and hyperkalemia were nonresponsive to traditional medical management; therefore, peritoneal dialysis was performed for emergent clinical stabilization. Peritoneal dialysis was conducted over 3 days and facilitated the patient to undergo laser lithotripsy of the offending ureteral obstruction. The dolphin made a full recovery following months of intensive medical treatment for complications from peritoneal dialysis and secondary peritonitis. This is the first documented case of successful, though complicated, peritoneal dialysis in a cetacean. Full article

Alveolar capillary dysplasia with misalignment of pulmonary veins (ACDMPV) is a rare, often fatal congenital disorder characterized by severe neonatal respiratory distress and associated with complex multisystem malformations. In approximately 90% of cases, the condition is linked to deletions or mutations affecting the FOXF1 gene or its upstream enhancer region on chromosome 16q24.1. This review analyzes reported prenatal cases with 16q24.1 deletion involving FOXF1, aiming to identify recurrent sonographic features and elucidate the underlying genomic and epigenetic mechanisms. We reviewed prenatal cases reported in the literature involving deletions of the 16q24.1 region, including the FOXF1 gene. Here, we expand the case series by reporting a fetus with increased nuchal translucency measuring 8 mm and a de novo 16q24.1 deletion. We identified nine prenatal cases with a 16q24.1 deletion, all involving the FOXF1 gene or its enhancer region. The main ultrasound findings included increased nuchal translucency and cystic hygroma during the first trimester, and cardiac, renal, and intestinal malformations from 20 weeks of gestation onward. Prenatal diagnosis of ACDMPV based solely on ultrasound findings is challenging. In most reported cases, the pregnancy was carried to term, with the diagnosis being confirmed by post-mortem histopathological examination. In the only case in which the pregnancy was terminated at 14 weeks’ gestation, histological examination of the fetal lungs, despite them being in the early stages of development, revealed misaligned pulmonary veins in close proximity to the pulmonary arteries and bronchioles. Evidence highlights the significance of non-coding regulatory regions in the regulation of FOXF1 expression. Differential methylation patterns, and possible contributions of parental imprinting, highlight the complexity of FOXF1 regulation. Early detection through array comparative genomic hybridization (array CGH) or next-generation sequencing to identify point mutations in the FOXF1 gene, combined with increased awareness of ultrasound markers suggestive of the condition, could improve the accuracy of prenatal diagnosis and genetic counseling. Further research into the epigenetic regulation of FOXF1 is crucial for refining recurrence risk estimates and improving genetic counseling practices. Full article

Objectives: The aim of the study was to assess the utility of contrast-enhanced ultrasound (CEUS), using both qualitative and quantitative perfusion analysis, in differentiating subtypes of renal cell carcinoma (RCC). Methods: This prospective, single-center study includes 91 patients with histologically confirmed RCC. We performed a CEUS within one week prior to nephrectomy. Qualitative parameters (enhancement pattern, heterogeneity, pseudocapsule) and quantitative perfusion metrics were assessed. Logistic regression models were developed to evaluate the diagnostic performance of CEUS in differentiating high-grade (clear cell RCC) from low-grade RCC (papillary and chromophobe). Results: Qualitative CEUS findings showed that hyperenhancement and isoenhancement were significantly associated with high-grade RCC (OR = 38.3 and OR = 7.8, respectively; p < 0.001 and p = 0.014). Hypoenhancement was predominant in low-grade RCC (80.0%). Quantitative parameters, including peak enhancement and wash-in/wash-out area under the curve, significantly differed between tumor grades (p < 0.001). A model using qualitative parameters alone achieved an AUC of 0.847 and 81.9% accuracy. Adding quantitative metrics marginally improved performance (AUC 0.912, accuracy 86.2%), though not significantly. Conclusions: CEUS provides valuable diagnostic information in differentiating RCC subtypes, with qualitative parameters alone demonstrating strong predictive power. While quantitative analysis slightly enhances diagnostic accuracy, its added value may be limited by technical challenges. Full article

Background and clinical significance: Ectopic ureters are a rare urinary tract malformation, typically diagnosed in childhood and infrequently in adulthood. The prenatal detection by ultrasound and magnetic resonance imaging (MRI) of this clinical entity has scarcely been reported. Careful foetal scanning during the late second and third trimester might provide clues and lead to prenatal detection. However, even the postnatal diagnosis is challenging, and often delayed towards adulthood, since the condition may present with nonspecific symptoms, leading to underdiagnosis or misdiagnosis. In female patients, approximately 25% of ectopic ureters open into the vagina. Due to the high risk of recurrent urinary tract infections and the potential development of uretero-hydronephrosis, timely diagnosis is essential, and prompt surgical correction is mandated. Case presentation: We report the case of a 33-year-old GII PI patient diagnosed with cystic dysplasia of the left foetal kidney at the 16 WG (weeks of gestation) scan. The malformation was consistent at 21 WG when karyotyping by amniocentesis identified a normal female molecular karyotype. MRI performed at 28 weeks confirmed the left renal dysplasia and raised the suspicion of an abnormal insertion of the left ureter into the vagina. After delivery, the vaginal ureteral ectopy was confirmed at 3 weeks postpartum via cystoscopy. Postpartum whole exome sequencing identified a variant of uncertain significance (VUS) mutation in the SOX 13 gene (SRY-box transcription factor 13). Renal scintigraphy performed 7 months postnatally identified a hypo/afunctional left kidney which led to the indication of nephrectomy by the paediatric urologist. The surgical intervention was performed at 8 months postpartum with a favourable outcome. Conclusions: Ectopic ureters are a pathology generating life-long morbidity and discomfort of the offspring and young adult. Awareness to this pathology must be raised among clinicians, especially regarding the potential detection by minute prenatal ultrasound examinations, followed by MRI to refine diagnosis. Postnatally, the persistence of suspicious yet unspecific symptoms, in both males and females, must trigger thorough imaging/cystoscopic examination to reach diagnosis and provide correct management. Full article

Introduction: Renal artery stenosis can significantly impact long-term graft survival rates following kidney transplant. Early recognition and management can improve the longevity of the kidney allograft. We aimed to evaluate the clinical role of duplex ultrasound in the diagnosis of renal artery stenosis (RAS). We also wanted to evaluate the current incidence of renal artery stenosis at our institute. Methods: A retrospective, consecutive series of 367 patients who underwent renal transplantation between 1 January 2020 and 30 December 2024 was conducted. We collected data regarding the recipients’ age, body mass index, and comorbidities. All patients diagnosed with renal artery stenosis were identified. The incidence of kidney transplant artery stenosis and presentation were recorded. All general physical parameters and laboratory data were collected and analyzed. Results: A total of 28 patients had initial suspicion of renal artery stenosis, documented via initial dedicated duplex ultrasound of the transplanted kidney. The initial mean systolic BP at initial US was 151 (99–213) mmHg, and mean creatinine was 2.43 (1.28–6.38) mg/dL. However, on repeat duplex ultrasound, three patients showed no features of renal artery stenosis and had no physical parameters consistent with RAS. A total of 25 patients diagnosed with RAS on initial duplex ultrasound underwent angiography. Twenty-four patients were confirmed with RAS on angiography, while one patient had a normal angiogram. Among patients diagnosed with TRAS, the mean resistive index was 0.71 ± 0.17 at the upper pole, 0.73 ± 0.19 at the mid pole, and 0.71 ± 0.21 at the lower pole. The mean peak systolic velocity was 462.57 ± 166.28 cm/s. Conclusions: Duplex ultrasound is an important initial tool for diagnosing transplant renal artery stenosis. An increase in peak systolic velocity was observed in our cohort; however, resistive indices were largely within acceptable limits. Management should be guided by clinical parameters (e.g., elevated systolic BP and rising creatinine) alongside imaging findings. Full article

Contrast-enhanced ultrasound and elastography are two ultrasound technologies that are becoming increasingly popular in the evaluation of different abdominal pathologies in children. The use of these technologies has expanded the diagnostic scope of ultrasound into areas that were traditionally covered by advanced imaging modalities such as computed tomography, magnetic resonance imaging, and fluoroscopy. In this review, we summarize the use of contrast-enhanced ultrasound and elastography in the evaluation of hepatic, renal, pancreatic, splenic, urinary tract, and scrotal pathologies in children. We describe the technical aspects, applications, and limitations, intending to make readers more acquainted with the technologies. Full article

The aim of this prospective study was to evaluate contrast-enhanced urosonography (CE-VUS) as an alternative to radiographic retrograde cystourethrography (RCUG) in the detection of vesicoureteral reflux (VUR) in young dogs. A total of 62 dogs, ranging in age from 6 weeks to 12 months, and 124 ureterorenal units (UUs) were investigated for VUR using RCUG and CE-VUS. After a baseline gray-scale ultrasound (US) of the urinary tract, a second-generation ultrasound contrast agent (UCA), diluted in a bottle of normal saline, was instilled into the urinary bladder via a catheter and CE-VUS was performed. VUR was detected when microbubbles were observed in the ureter and/or in the renal pelvis. In addition, RCUG was performed on the same day. The findings obtained by CE-VUS and RCUG were concordant in 117/124 UUs (94.35%). No reflux was detected in 101/124 UUs (81.45%) using both methods. With RCUG as the standard of reference, the sensitivity of CE-VUS was 94.12%, and the specificity was 94.39%. The positive predictive value was 72.73%, and the negative predictive value was 99.02%. CE-VUS is highly sensitive for the detection of VUR in young dogs. Full article

Introduction: Fraser syndrome (FS) is a rare autosomal recessive disorder. However, the clinical presentation remains variable. Diagnosis is based on a series of major and minor clinical criteria that can be supported by genetic tests. Prenatal diagnosis remains challenging. Methods: Herein, we reported a case of Fraser syndrome that was missed by ultrasound and diagnosed late at birth. The newborn presented with cryptophthalmos–syndactyly syndrome and absence of the right kidney. Based on a literature review of articles from the past 20 years, the authors found 40 cases, including indexed cases on PUBMED, Scopus, Web of Science, and Scholar using keywords related to “Fraser syndrome”. Through this report, we discuss the polymalformative syndrome, the clinical and paraclinical aspects of this syndrome, its clinical management, and highlight the importance of prenatal diagnosis in the light of research. Results: Our study found that consanguine parents (41.0%) were increasing risk factors for FS and poor socio-economic status delayed the early detection of FS. Among the 40 cases, 27 cases were detected postnatally. More than half of the cases resulted in poor perinatal outcomes. The common findings were cryptophthalmos (87.5%), syndactyly (87.5%), renal abnormalities (55.5%), and genital abnormalities (42.5%). Conclusions: A prenatal diagnosis of Fraser syndrome is still difficult. Thus, a counseled ultrasound scan at a specialized center should be recommended in suspected cases with indirect signs and risk factors of consanguinity. Full article

Background/Objectives: The course of treatment for renal artery stenosis following renal transplantation depends on the severity of the condition. Mild cases are typically managed medically, while more significant stenosis with flow limitation and graft dysfunction requires percutaneous intervention. Surgical treatment is generally reserved as a last resort. This study aimed to evaluate the outcomes of interventional radiology in managing renal artery stenosis at our transplant center. Methods: The electronic medical records of patients who underwent renal transplantation at our center between January 2020 and December 2024 were reviewed to identify cases of renal artery stenosis and their subsequent management through interventional radiology. Sociodemographic and clinical data were collected for both recipients and donors. Data analysis was performed using SPSS version 26. Results: Out of the total 368 patients who received renal allograft at our center from January 2020 to December 2024, 25 patients were confirmed with duplex ultrasound to have renal artery stenosis. The majority of affected patients were African American, had Class I Obesity and presented with cardiovascular co-morbidities. The mean time from transplant to the diagnosis of RAS was 4.25 (SD ± 3.81) months. The mean serum creatinine level at presentation was 2.54 (SD ± 1.21 mg/dL). All 25 patients underwent digital subtraction angiography, and 24 patients were confirmed to have renal artery stenosis requiring further intervention. The creatinine levels at one week, three months and one year post-intervention were 2.12 (SD ± 1.00), 1.83 (SD ± 0.63) and 2.15 (SD ± 1.68) mg/dL, respectively. Conclusions: Percutaneous interventional treatment for renal artery stenosis is associated with improvements in hemodynamic parameters and the stabilization of allograft function. Follow-up is needed to monitor for the potential occurrence of restenosis. Full article

Unilateral renal agenesis (URA) is a urinary tract congenital anomaly characterized by a congenital absence or early developmental arrest of only one kidney. In the presence of a normal contralateral kidney, URA is typically considered a condition of minimal clinical significance as the solitary kidney often undergoes hypertrophy and can sufficiently perform the needed renal function after birth. However, postnatal studies suggest that URA has a significant association with other urinary and extra-urinary anomalies and may have implications for long-term health. This descriptive review focuses on the perinatal aspects of URA, emphasizing the main ultrasound findings to establish the prenatal diagnosis and to guide perinatal management. The pediatric implications of this diagnosis, particularly the high prevalence of long-term complications including hypertension, proteinuria, and a decreased glomerular filtration rate, are also briefly reviewed. URA is consistently associated with other ipsilateral urogenital anomalies. In females, there is a significant association with uterine anomalies that has significant implications for subsequent reproductive function. In males, the prevalence of both urinary and genital anomalies is also increased, which may also have implications for future fertility. Prenatal ultrasound offers the possibility of early diagnosis and parental counseling, which may result in timely intervention to reduce contralateral renal damage, prevent severe urogenital manifestations and co-morbidities, and improve fertility and the quality of life. Full article

Background: Vascular imaging is essential for clinical practice, research, and the diagnosis and management of vascular diseases. Super-resolution ultrasound (SRUS) imaging is an emerging high-resolution imaging technique with broad applications in soft tissue vascular imaging. However, the impact of biological and clinical variables on its imaging accuracy is currently unknown. This study investigates these factors in an animal model and compares SRUS with contrast-enhanced µCT. Methods: Kidney scans from 29 Zucker rats (Zucker Diabetic Fatty and Zucker Lean) were retrospectively analysed. The left kidney was imaged in vivo using SRUS during microbubble infusion, then filled with Microfil and excised for ex vivo µCT. SRUS parameters and clinical variables were analysed, and SRUS scans were co-registered with µCT to compare vascular density measurements. Results: Mean arterial blood pressure and anaesthesia time showed significant linear relationships with SRUS microbubble detection and vascular track reconstruction. The anaesthesia time was also strongly correlated with vascular density measurement. Visualisation and velocity estimations of renal arteries were limited with SRUS. Ultrasound signal attenuation had significant impacts, particularly in cortical far-field imaging. Despite differences between kidney regions, the vascular density distribution did not differ considerably between SRUS and µCT datasets for whole-kidney imaging. Conclusions: This study outlines key factors SRUS users must consider for optimal technique use. Careful region selection and control of clinical variables ensure more reliable and comparable images. Further research is necessary to translate these findings from a rat model into clinical application. Full article

Background/Objectives: Ultrasound Doppler diagnostics is a modern diagnostic method, routinely used to determine the blood flow velocity in vessels in clinical practice and scientific experiments. The aim of this study was to investigate hemodynamics and identify blood flow velocity norms for various age groups of animals in the range of two to six months. Methods: This study presents the blood flow velocity characteristics in different areas of the abdominal aorta of 30 growing Wistar rats two to six months old. The data from senile rats aged 24 months were used as a reference, since these animals should not show any changes in hemodynamics associated with the active growth of the organism. Ultrasound screening in the group of growing rats was performed monthly, and blood flow velocity was measured at three points: proximal to the renal arteries, distal to the renal arteries, and before the bifurcation zone of the abdominal aorta. Conclusions: The obtained data can be used as normative values in in vivo small-diameter tissue-engineered vascular graft (TEVG) studies to assess changes in hemodynamics. Full article

Background/Objectives: Pancreatic neoplasms, including adenocarcinoma, pancreatic neuroendocrine tumors (pNETs), intraductal papillary mucinous neoplasms (IPMNs), and high-grade cystic lesions, often require surgical resection as a form of curative treatment. However, comorbidities and high-risk features may preclude surgery. Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) has emerged as a minimally invasive alternative with proven cytoreductive efficacy in solid tumors. This case series evaluates the safety and efficacy of EUS-RFA in patients with various unresectable, non-metastatic pancreatic neoplasms. Methods: A retrospective review was conducted on eight patients who underwent EUS-RFA at our institutions between July 2021 and February 2025. All patients were deemed unsuitable surgical candidates due to comorbidities such as advanced age, cardiovascular disease, renal insufficiency, and COPD or due to patient resistance to surgical intervention. EUS-RFA was performed using a 19-gauge RFA needle (Taewoong Corporation). Follow-up imaging was conducted 3 to 6 months after the completion of RFA treatment. Results: All eight patients demonstrated a good to excellent response in terms of tumor size reduction. The most notable response was observed in a patient with pNET, resulting in complete resolution from 15.6 × 12.0 mm to 0.0 × 0.0 mm after two RFA treatments. Other neoplasms, including pancreatic adenocarcinoma and intraductal papillary mucinous neoplasms (IPMNs), also demonstrated significant reductions. Mild post-procedure complications, including pancreatitis and abdominal pain, were noted in three cases. Conclusions: EUS-RFA is a promising alternative for managing unresectable pancreatic neoplasms in high-risk patients. Our findings support its use across various tumor types with favorable outcomes and minimal complications, reinforcing its role in expanding therapeutic options beyond surgery. Full article

Background: Serum uric acid and serum creatinine ratio (SUA/sCr) is strongly linked to increased cardiovascular risk. Atherosclerotic renal artery stenosis (ARAS) is a secondary cause of hypertension and is associated with ischemic nephropathy, congestive heart failure, accelerated cardiovascular disease, and autonomic dysfunction. The aim of this study was to investigate whether SUA levels and SUA/sCr could represent markers of autonomic dysfunction and increased left ventricular mass index (LVMI) in patients with ARAS. Methods: Patients diagnosed with ARAS were enrolled in the study. All patients underwent clinical evaluation, biochemical analysis, 24 h electrocardiogram (ECG), and Renal Doppler Ultrasound with renal resistive index parameters. Heart rate variability for global autonomic dysfunction was assessed through the analysis of a 24 h ECG to detect the standard deviation of normal-to-normal RR intervals (SDNN). Echocardiographic measurement of LVMI was performed. Results: A total of 27 patients (F = 16 (59%), median age 67 years (IQR 60–77)) diagnosed with ARAS were enrolled in the study. We found a statistically significant negative linear correlation between SUA/sCr and SDNN (r = −0.519, p < 0.01). We found a statistically significant positive linear correlation between SUA/sCr and LVMI (r = 0.413, p < 0.05). Median SDNN was significantly lower in patients with SUA ≥ 5.6 mg/dL than in patients with SUA < 5.6 mg/dL (94.2 (IQR 86.8–108.1) vs. 112.8 (IQR 108.9–114.7), p < 0.01). Median LVMI was significantly higher in patients with SUA ≥ 5.6 mg/dL compared to patients with SUA < 5.6 mg/dL (133 g/m² (IQR 120–149) vs. 111 g/m² (IQR 99–129), p < 0.05). Conclusion: In patients with ARAS, SUA/sCr is associated with autonomic dysfunction and LVMI in ARAS patients. The ratio and related cut-off value of SUA/sCr could represent a useful biomarker to evaluate cardiovascular risk in ARAS patients. Full article