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Diagnostic imaging allows for accurate and early recognition of acute renal pathologies, thus allowing for appropriate clinical triage, life-saving treatments, and preservation of renal function. In this review, we discuss the clinical... more
Diagnostic imaging allows for accurate and early recognition of acute renal pathologies, thus allowing for appropriate clinical triage, life-saving treatments, and preservation of renal function. In this review, we discuss the clinical presentation and imaging findings of renal emergencies with infectious, hemorrhagic, vascular, and traumatic etiologies.
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Purpose: Preoperative assessment of T3a renal-cell-carcinoma (RCC) in absence of main renal vein involvement or lymph node enlargement is challenging but has potential implications for counseling and prognosis. Materials and Methods: A... more
Purpose: Preoperative assessment of T3a renal-cell-carcinoma (RCC) in absence of main renal vein involvement or lymph node enlargement is challenging but has potential implications for counseling and prognosis. Materials and Methods: A retrospective review of 1129 cT1-T3aN0M0 RCC patients managed with partial/radical nephrectomy (PN/RN) in our institution (2012-2014) was performed. Exclusion criteria included radiological evidence of main renal vein involvement or substantial lymphadenopathy. Eleven radiological findings suggestive of aggressive tumor biology or invasive phenotype based on prior literature were assessed for correlation with pT3a status. These included perinephric-findings (stranding, enhancing-nodule, collateral-vessels, or irregular-perinephric-tumor-contour), findings within the sinus (stranding, collecting-system invasion, branch-vein enlargement, or irregular-tumor-sinus-border [ITSB]), and tumor-necrosis, infiltrative-features, and tumor-size. Radiological asse...
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Percent parenchymal mass-preserved (PPMP) is the primary determinant of functional outcomes after partial nephrectomy (PN). Accurate methods for predicting PPMP based on preoperative imaging could facilitate patient counseling. 428 PN... more
Percent parenchymal mass-preserved (PPMP) is the primary determinant of functional outcomes after partial nephrectomy (PN). Accurate methods for predicting PPMP based on preoperative imaging could facilitate patient counseling. 428 PN patients with necessary studies to assess ipsilateral parenchymal mass/function preserved were evaluated. Preoperative/postoperative ipsilateral parenchymal mass were measured from contrast-enhanced CT<2 months prior and 3-12 months after PN and actual-PPMP was determined. Ipsilateral-PPMP and final global-GFR were estimated based on preoperative imaging using subjective estimation (SE), quantitative estimation (QE), or estimation derived from contact surface area (CSA) or R.E.N.A.L. Median tumor diameter was 3.5cm. Median CSA/R.E.N.A.L. were 24cm and 8, respectively. Median actual ipsilateral-PPMP and percent global-GFR preserved were 84%/89%, respectively. Median estimated ipsilateral-PPMP was 85%/87%/88%/83% based on SE/QE/CSA/R.E.N.A.L., respect...
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Renovascular hypertension is the most common type of secondary hypertension and is estimated to have a prevalence between 0.5% and 5% of the general hypertensive population, and an even higher prevalence among patients with severe... more
Renovascular hypertension is the most common type of secondary hypertension and is estimated to have a prevalence between 0.5% and 5% of the general hypertensive population, and an even higher prevalence among patients with severe hypertension and end-stage renal disease, approaching 25% in elderly dialysis patients. Investigation for renal artery stenosis is appropriate when clinical presentation suggests secondary hypertension rather than primary hypertension, when there is not another known cause of secondary hypertension, and when intervention would be carried out if a significant renal artery stenosis were identified. The primary imaging modalities used to screen for renal artery stenosis are CT, MRI, and ultrasound, with the selection of imaging dependent in part on renal function. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guidelin...
Research Interests: Radiology, Urology, Evidence Based Medicine, US, MRI, and 13 moreMedicine, Humans, United States, Ct, AUC, Diagnostic Imaging, Clinical Sciences, Public health systems and services research, Cardiovascular Diseases, Renal artery stenosis, Appropriate Use Criteria, Secondary Hypertension, and Renovascular hypertension
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Purpose To compare the effectiveness of metastatic tumor response evaluation with computed tomography using computer-assisted versus manual methods. Materials and Methods In this institutional review board–approved, Health Insurance... more
Purpose To compare the effectiveness of metastatic tumor response evaluation with computed tomography using computer-assisted versus manual methods. Materials and Methods In this institutional review board–approved, Health Insurance Portability and Accountability Act–compliant retrospective study, 11 readers from 10 different institutions independently categorized tumor response according to three different therapeutic response criteria by using paired baseline and initial post-therapy computed tomography studies from 20 randomly selected patients with metastatic renal cell carcinoma who were treated with sunitinib as part of a completed phase III multi-institutional study. Images were evaluated with a manual tumor response evaluation method (standard of care) and with computer-assisted response evaluation (CARE) that included stepwise guidance, interactive error identification and correction methods, automated tumor metric extraction, calculations, response categorization, and data...
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Most men with hematospermia or hemospermia (HS) are young (<40 years of age), presenting with transient or episodic HS without other signs or symptoms of disease. The condition is self-limiting in most cases and idiopathic in nature.... more
Most men with hematospermia or hemospermia (HS) are young (<40 years of age), presenting with transient or episodic HS without other signs or symptoms of disease. The condition is self-limiting in most cases and idiopathic in nature. When a cause can be identified, infections of the urogenital tract are the most common. Imaging does not play a role in this patient population. In older men (>40 years of age), clinical screening for prostate cancer is advised. Furthermore, when HS is persistent or has symptoms, causes include obstruction or stricture at the level of the verumontanum, calcifications or calculi in the prostate, ejaculatory ducts or seminal vesicles, and cysts arising within these structures. Noninvasive imaging, predominantly transrectal ultrasound (TRUS) and MRI, can be used in men of any age with persistent or refractory HS, or other associated symptoms or signs. TRUS is considered as the first-line imaging with MRI used when TRUS is inconclusive or negative. Th...
Research Interests: Radiology, Magnetic Resonance Imaging, Medicine, Humans, Ultrasonography, and 11 moreUnited States, Male, Urinary Tract Infections, Clinical Sciences, Public health systems and services research, Age Factors, X ray Computed Tomography, GuideLine, Lower Urinary Tract Symptoms, Prostatic neoplasms, and Prostatic diseases
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Research Interests: Biomarkers, Acute kidney injury, Medicine, Linear models, Multivariate Analysis, and 15 moreHumans, Kidney, Ischemia, Female, Male, Renal Function, Clinical Sciences, Aged, Middle Aged, Retrospective Studies, Chi Square Distribution, Nephrectomy, Logistic Models, Creatinine, and Recovery of Function
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Research Interests: Radiology, Adolescent, Medicine, Humans, Male, and 6 moreDifferential Diagnosis, Clinical Sciences, Middle Aged, Scrotum, Adult, and Torsion
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Research Interests: Oncology, Medicine, Humans, Female, Renal cell Carcinoma, and 15 moreMale, Clinical Sciences, Aged, Middle Aged, Adult, Retrospective Studies, Pyridines, Disease Progression, Sensitivity and Specificity, Contrast Media, Angiogenesis inhibitors, Neoplasm metastasis, Niacinamide, Metastatic Renal Cell Carcinoma, and Response evaluation criteria in solid tumors
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Research Interests: Gastroenterology, Magnetic Resonance Imaging, MRI, Medicine, Humans, and 15 moreFemale, Male, Ct, Alcohol Consumption, Clinical Sciences, Middle Aged, Fatty Liver, Adult, NASH, Computerized tomography, Liver Disease, Neurosciences, Aspartate Aminotransferase, Magnetic resonance image, and Liver biopsy
Adrenal incidentalomas (AIs) are found in approximately 4% of patients undergoing abdominal imaging, with peak prevalence in the sixth and seventh decades of life. Detection of AI warrants clinical, biochemical, and radiological... more
Adrenal incidentalomas (AIs) are found in approximately 4% of patients undergoing abdominal imaging, with peak prevalence in the sixth and seventh decades of life. Detection of AI warrants clinical, biochemical, and radiological evaluation to establish its secretory status and risk of malignancy. Careful review of the lipid content, size, and imaging phenotype of an adrenal mass is needed to evaluate the risk for malignancy. Identification of an AI may be an opportunity to identify an underlying secretory tumor that may have been otherwise unrecognized. A practical approach to investigation and follow-up of AIs is presented in this article.
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Laparoscopic renal cryoablation is a developmental minimally invasive nephron-sparing treatment alternative for highly select patients with small renal tumors. We present our evolving experience with this procedure. Thirty-two patients... more
Laparoscopic renal cryoablation is a developmental minimally invasive nephron-sparing treatment alternative for highly select patients with small renal tumors. We present our evolving experience with this procedure. Thirty-two patients (34 tumors) with a mean tumor size of 2.3 cm on preoperative computed tomography underwent laparoscopic renal cryoablation. As dictated by the tumor location, cryoablation was performed by either the retroperitoneal (n = 22) or the transperitoneal (n = 10) laparoscopic approach using real-time ultrasound monitoring. A double freeze-thaw cycle was routinely performed. The mean surgical time was 2.9 hours, cryoablation time 15.1 minutes, and blood loss 66.8 mL. For a mean intraoperative ultrasonographic tumor size of 2 cm, the mean cryolesion size was 3.2 cm. The hospital stay was less than 23 hours in 22 (69%) of 32 patients. Sequential magnetic resonance imaging scans demonstrated a gradual contraction in the mean diameter of the cryolesions. Of the 20 patients who underwent a 1-year follow-up magnetic resonance imaging scan, the cryoablated tumor was no longer visible in 5. Of note, 23 patients have now undergone a 3 to 6-month follow-up computed tomography-directed biopsy of the cryoablated tumor site; the biopsy was negative for cancer in all 23 patients. No evidence of local or port-site recurrence was found during a mean follow-up of 16.2 months. Critical long-term data regarding laparoscopic renal cryoablation, a developmental technique, are awaited. However, our initial experience is cautiously optimistic. Despite its significant potential for false-negative results, it is encouraging that the follow-up computed tomography-directed needle biopsies at 3 to 6 months were negative for cancer in 23 of 23 patients.
Research Interests: Radiology, Computed Tomography, Magnetic Resonance Imaging, Medicine, Biopsy, and 15 moreHumans, Renal cell Carcinoma, Real Time, Clinical Sciences, Aged, Middle Aged, Adult, Cryosurgery, Blood Loss, Minimally Invasive, Laparoscopy, Cryoablation, False Negative, Magnetic resonance image, and Intraoperative Period
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Renal cell carcinoma (RCC) is a common cancer that is increasing in incidence because of the increased prevalence of risk factors, including tobacco use, hypertension, and obesity, and the improved detection of these tumors due to... more
Renal cell carcinoma (RCC) is a common cancer that is increasing in incidence because of the increased prevalence of risk factors, including tobacco use, hypertension, and obesity, and the improved detection of these tumors due to increased use of imaging. Localized renal cancer now accounts for more than 60%-70% of new RCC cases. Renal masses suggestive of cancer include enhancing solid renal lesions and Bosniak III and IV complex cystic lesions. Most of these tumors are detected incidentally, and many are slow growing with little propensity to metastasize. Radiologists have a vital role in evaluation of these tumors and subsequent patient counseling. Options for managing RCC include radical nephrectomy (RN), partial nephrectomy (PN), thermal ablation, and active surveillance. However, historically, the use of these strategies has varied among practices. Improved understanding of the biologic features of these tumors and data indicating the heterogeneous clinical course of many cli...
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ABSTRACT
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An elevation of fractionated plasma or urinary metanephrine (MN) or nor-metanephrine (NMN), collectively called metanephrines (MN and NMN),... more
An elevation of fractionated plasma or urinary metanephrine (MN) or nor-metanephrine (NMN), collectively called metanephrines (MN and NMN), &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;4-fold above the upper limit of normal (ULN) is usually considered to be diagnostic for pheochromocytoma (PHEO). There are a greater number of false positive results when the elevations are more modest. To identify biochemical and radiological features in PHEOs with modest elevations (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;4-fold above ULN) of metanephrines. We retrospectively reviewed the charts of 112 patients with PHEO (10% extra-adrenal) and 208 patients with a non-PHEO adrenal mass operated from 1997-2011, who had metanephrines measured pre-operatively. We divided PHEO into group 1 (n = 90) with metanephrines ≥4-fold ULN and group 2 (n = 22) with metanephrines &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;4-fold ULN. The non-PHEO group was designated as group 3. The median (range) tumour size in group 1 and group 2 was 4·8 cm (1·7-22) and 3·0 cm (1·7-5) respectively (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0·001). All patients with PHEO in group 2 had a tumour &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;5 cm in size. The MN fraction was elevated in about 65% of groups 1 and 2; only 2 (1%) patients in group 3 had an elevated urinary MN fraction, and none were associated with an elevated plasma MN fraction. All PHEOs had a pre-contrast attenuation ≥17 Hounsfield Units (HU). Modest elevations…
Research Interests: Urology, Adolescent, Medicine, Humans, Child, and 15 moreInternal Medicine, Female, Male, Young Adult, Pheochromocytoma, Clinical Sciences, Aged, Middle Aged, Adult, Urinary System, Retrospective Studies, Clinical Endocrinology, Case Control Studies, Multidetector Computed Tomography, and Paediatrics and reproductive medicine
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Research Interests: Medicine, Humans, Female, Male, American, and 7 moreClinical Sciences, Aged, Middle Aged, Adult, Cryosurgery, Laparoscopy, and Cryoablation
Research Interests: Radiology, Magnetic Resonance Imaging, Adolescent, Medicine, Humans, and 15 moreFemale, Male, Hepatocellular Carcinoma, Clinical Sciences, Middle Aged, Image Enhancement, Adult, Retrospective Studies, Hepatocyte, Adenoma, Receiver Operating Characteristic, Area Under Curve, Contrast Media, Liver neoplasms, and focal nodular hyperplasia
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Objective: The aim of this study was to analyze the incidence of and risk factors for adrenocortical carcinoma (ACC) in adrenal incidentaloma (AI). Summary of Background Data: AI guidelines are based on data obtained with old-generation... more
Objective: The aim of this study was to analyze the incidence of and risk factors for adrenocortical carcinoma (ACC) in adrenal incidentaloma (AI). Summary of Background Data: AI guidelines are based on data obtained with old-generation imaging and predominantly use tumor size to stratify risk for ACC. There is a need to analyze the incidence and risk factors from a contemporary series. Methods: This is a retrospective review of 2219 AIs that were either surgically removed or nonoperatively monitored for ≥12 months between 2000 and 2017. Multivariate logistic regression was performed to define risk factors. ROC curves constructed to determine optimal size and attenuation cut-offs for ACC. Results: 16.8% of AIs underwent upfront surgery and rest initial nonoperative management. Of conservatively managed patients, an additional 7.7% subsequently required adrenalectomy. Overall, ACC incidence in AI was 1.7%. ACC rates by size were 0.1%, 2.4%, and 19.5% for AIs of <4, 4 to 6, and >...
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Renal transplantation is the treatment of choice in patients with end-stage renal disease because the 5-year survival rates range from 72% to 99%. Although graft survival has improved secondary to the introduction of newer... more
Renal transplantation is the treatment of choice in patients with end-stage renal disease because the 5-year survival rates range from 72% to 99%. Although graft survival has improved secondary to the introduction of newer immunosuppression drugs and the advancements in surgical technique, various complications still occur. Ultrasound is the first-line imaging modality for the evaluation of renal transplants in the immediate postoperative period and for long-term follow-up. In addition to depicting many of the potential complications of renal transplantation, ultrasound can also guide therapeutic interventions. Nuclear medicine studies, CT, and MRI are often helpful as complementary examinations for specific indications. Angiography remains the reference standard for vascular complications and is utilized to guide nonsurgical intervention. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annua...