Guidelines recommend adrenal venous sampling to determine disease laterality in primary aldosteronism. Adrenocorticotropic hormone (ACTH) stimulation clearly improves the likelihood of successful ...adrenal vein catheterization but may lead to a decrease in lateralization rates. To examine the impact of ACTH on lateralization, we performed a retrospective analysis of 340 patients with confirmed primary aldosteronism who underwent adrenal venous sampling with a single interventional radiology team using a protocol of sampling both before and after an ACTH bolus. In addition to this original research, we conducted a review of similar studies from the past 5 years to develop a consensus on the impact of ACTH on lateralization for primary aldosteronism. In the original research analysis, following a bolus of ACTH, 58% of patients had a decline in lateralization index which led to discordance between the pre-ACTH and post-ACTH classifications of lateralization in up to 26% of cases. The majority of discordant cases were due to reclassification from unilateral disease pre-ACTH to bilateral disease post-ACTH. In patients who already lateralized with unstimulated sampling, the response to ACTH did not have any impact on surgical outcomes. In a review of contemporary studies, we identified 11 similar studies in the past 5 years, of which 10 reported either no change or a decrease in lateralization index following ACTH, resulting in ≈25% discordance between unstimulated and stimulated lateralization rates. We conclude that ACTH stimulation during adrenal venous sampling can underestimate surgically remediable primary aldosteronism and recommend that the role of ACTH be limited primarily to enhancing selectivity.
To assess the feasibility and safety of using computed tomography (CT) guidance for ablation of prostate cancer in the salvage setting.
This institutional review board-approved retrospective study of ...consecutive patients who presented with prostate cancer recurrence and underwent percutaneous CT-guided cryoablation was conducted between July 2020 and September 2022. A total of 18 patients met the inclusion criteria, and a total of 19 procedures were performed. Demographic details; preablation and postablation urinary, rectal, and erectile function assessment; procedure details; and preoperative and postoperative imaging findings and prostate-specific antigen (PSA) values were recorded.
The mean treated tumor size was 15.7 mm ± 6.2. Technical success was achieved in 18 of the 19 procedures (94.7%), with 1 procedure aborted due to inability to obtain a safe plane. The mean follow-up time was 10.0 months (range, 2.3-26.7 months) at the time of manuscript preparation. The mean PSA before ablation was 8.1 ng/mL ± 9.3, and postablation PSA nadir was 2.6 ng/mL ± 4.0 (P = .002). Of the 18 patients who had postoperative imaging, 16 (88.9%) had a complete response (ie, no evidence of residual disease), and 2 (11.1%) patients had residual disease. Overall, 16 (88.9%) of the 18 treated patients demonstrated a PSA and/or imaging response to ablation. Mild adverse events occurred in 4 (22%) of the 18 cases.
CT-guided cryoablation appears to be a technically feasible, safe option for treating locally recurrent prostate cancer.
Guidelines recommend adrenal venous sampling (AVS) to determine disease laterality in primary aldosteronism. Adrenocorticotropic hormone (ACTH) stimulation clearly improves the likelihood of ...successful adrenal vein catheterization, but may lead to a decrease in lateralization rates. To examine the impact of ACTH on lateralization, we performed a retrospective analysis of 340 patients with confirmed primary aldosteronism who underwent AVS with a single interventional radiology team using a protocol of sampling both before and after an ACTH bolus. In addition to this original research, we conducted a review of similar studies from the last five years to develop a consensus on the impact of ACTH on lateralization for primary aldosteronism. In the original research analysis, following a bolus of ACTH, 58% of patients had a decline in lateralization index (LI) which led to discordance between the pre- and post-ACTH classifications of lateralization in up to 26% of cases. The majority of discordant cases were due to reclassification from unilateral disease pre-ACTH to bilateral disease post-ACTH. In patients who already lateralized with unstimulated sampling, the response to ACTH did not have any impact on surgical outcomes. In a review of contemporary studies, we identified 11 similar studies in the last 5 years, of which 10 reported either no change or a decrease in LI following ACTH, resulting in approximately 25% discordance between unstimulated and stimulated lateralization rates. We conclude that ACTH-stimulation during AVS can underestimate surgically remediable primary aldosteronism and recommend that the role of ACTH be limited primarily to enhancing selectivity.
ACTH-stimulated adrenal venous sampling for primary aldosteronism can decrease lateralization rates and may lead to fewer patients being referred for potentially curative surgery.
Primary aldosteronism is an underdiagnosed cause of hypertension. Although inadequate screening is one reason for underdiagnosis, another important contributor is that clinicians may inappropriately ...exclude the diagnosis when screening aldosterone concentrations fall below traditionally established thresholds. We evaluated the intra-individual variability in screening aldosterone concentrations and aldosterone-to-renin ratios, and how this variability could impact case detection, among 51 patients with confirmed primary aldosteronism who had two or more screening measurements of renin and aldosterone on different days. There were a total of 137 screening measurements with a mean of 3 (range 2–6) per patient. The mean intra-individual variability, expressed as coefficients of variation, was 31% for aldosterone and 45% for the aldosterone-to-renin ratio. Aldosterone concentrations ranged from 4.9 to 51 ng/dL; 49% of patients had at least one aldosterone measurement below 15 ng/dL, 29% had at least two aldosterone measurements below 15 ng/dL, and 29% had at least one measurement below 10 ng/dL. Individual aldosterone-to-renin ratios ranged from 8.2 to 427 ng/dL per ng/mL/h; 57% had at least one ratio below 30 ng/dL per ng/mL/h, 27% had at least two ratios below 30 ng/dL per ng/mL/h, and 24% had at least one ratio below 20 ng/dL per ng/mL/h. Aldosterone concentrations and aldosterone-to-renin ratios are highly variable in patients with primary aldosteronism, with many screening values falling below conventionally accepted diagnostic thresholds. The diagnostic yield for primary aldosteronism may be substantially increased by re-calibrating the definition of a ‘positive screen’ to include more liberal thresholds for aldosterone and the aldosterone-to-renin ratio.
To study the effects of the surrounding electrical microenvironment and local tissue parameters on the electrical parameters and outcome of irreversible electroporation (IRE) ablation in porcine ...muscle, kidney, and liver tissue.
Animal Care and Use Committee approval was obtained, and National Institutes of Health guidelines were followed. IRE ablation (n = 90) was applied in muscle (n = 44), kidney (n = 28), and liver (n = 18) tissue in 18 pigs. Two electrodes with tip exposure of 1.5-2 cm were used at varying voltages (1500-3000 V), pulse repetitions (n = 70-100), pulse length (70-100 µsec), and electrode spacing (1.5-2 cm). In muscle tissue, electrodes were placed exactly parallel, in plane, or perpendicular to paraspinal muscle fibers; in kidney tissue, in the cortex or adjacent to the renal medulla; and in liver tissue, with and without metallic or plastic plates placed 1-2 cm from electrodes. Ablation zones were determined at gross pathologic (90-120 minutes after IRE) and immunohistopathologic examination (6 hours after) for apoptosis and heat-shock protein markers. Multivariate analysis of variance with multiple comparisons and/or paired t tests and regression analysis were used for analysis.
Mean (± standard deviation) ablation zones in muscle were 6.2 cm ± 0.3 × 4.2 cm ± 0.3 for parallel electrodes and 4.2 cm ± 0.8 × 3.0 cm ± 0.5 for in-plane application. Perpendicular orientation resulted in a cross-shaped zone. Orientation significantly affected IRE current applied (28.5-31.7A for parallel, 29.5-39.7A for perpendicular; P = .003). For kidney cortex, ovoid zones of 1.5 cm ± 0.1 × 0.5 cm ± 0.0 to 2.5 cm ± 0.1 × 1.3 cm ± 0.1 were seen. Placement of electrodes less than 5 mm from the medullary pyramids resulted in treatment effect arcing into the collecting system. For liver tissue, symmetric 2.7 cm ± 0.2 × 1.4 cm ± 0.3 coagulation areas were seen without the metallic plate but asymmetric coagulation was seen with the metallic plate.
IRE treatment zones are sensitive to varying electrical conductivity in tissues. Electrode location, orientation, and heterogeneities in local environment must be considered in planning ablation treatment. Online supplemental material is available for this article.
Abstract
Background
Normal-appearing adrenal glands on cross-sectional imaging may still be the source of aldosterone production in primary aldosteronism (PA).
Methods
We evaluated the prevalence of ...aldosterone production among morphologically normal-appearing adrenal glands and the impact of this phenomenon on interpretations of localization studies and treatment decisions. We performed a retrospective cohort study of PA patients with at least 1 normal adrenal gland and reanalyzed contemporary studies to assess interpretations of imaging and adrenal venous sampling (AVS) at the individual patient and adrenal levels.
Results
Among 243 patients, 43 (18%) had bilateral normal-appearing adrenals and 200 (82%) had a unilateral normal-appearing adrenal, for a total of 286 normal-appearing adrenal glands. 38% of these normal-appearing adrenal glands were a source of aldosteronism on AVS, resulting in discordance between imaging and AVS findings in 31% of patients. Most patients with lateralizing PA underwent curative unilateral treatment (80%); however, curative treatment was pursued in 92% of patients who had concordant imaging-AVS results but in only 38% who had discordant results (P < 0.05). In young patients, imaging-AVS discordance was detected in 32% of those under 45 years and 21% of those under 35 years. Among 20 contemporary studies (including 4,904 patients and 6,934 normal-appearing adrenal glands), up to 64% of normal-appearing adrenals were a source of aldosteronism resulting in 31% of patients having discordant results.
Conclusions
Morphologically normal-appearing adrenal glands are commonly the source of aldosterone production in PA, even among young patients. The lack of awareness of this issue may result in inappropriate treatment recommendations.
Graphical Abstract
Graphical Abstract
Enhancing hydrocarbon recovery is an ongoing practice in the petroleum industry. Multiple approaches are developed and proved their effectiveness in increasing reservoirs recovery. One of the recent ...approaches is the Low Salinity Water Injection which is known in the industry by “LoSal”. The determination of the optimum low salinity of the injected water and the mechanism behind its ability to enhance the hydrocarbon recovery are still the subjects of interest for many researchers and industry professionals. Despite the value of the LoSal water injection, it brings with it a considerable challenge to the future formation evaluation, namely the determination of the fluids’ saturation. The mixing of the low salinity injected water with the original high-salinity formation water creates variable water salinity across the reservoir. This is known in the industry by the “mixed-salinity” problem. The horizontal and the vertical heterogeneity of the permeability and porosity across the reservoir is the main factor that controls the “mixed-salinity” distribution in the injected volume. The challenge of calculating the fluids’ saturation exists for both the infill drilling wells and the monitoring wells. For the infill drilling wells, the saturation calculations require accurate formation water resistivity values,
R
w
, which became variable due to the mixed-salinity. For the monitoring wells, the fluids saturation calculations require accurate formation water sigma absorption, Σ
w
,
which also became variable for the same reason. The inability to determine the current
R
w
and Σ
w
on foot-by-foot basis results in incorrect calculations of the water and hydrocarbon saturations. This creates an economic burden on the reservoir management. The existing methods to interpret the fluids saturation in mixed-salinity reservoirs face the challenges of accuracy, effect of borehole environment and high-data acquisitions cost. A forward modeling is developed to illustrate the problem and its impact on the reservoir decisions making process. A solution to the challenges is proposed, investigated, and proved both theoretically and in the laboratory. The proposed solution is based on lowering the LoSal water resistivity, prior to injection, to be equal to the original formation water resistivity without changing its low salinity. This is achieved by mixing the LoSal water with either acid or alkaline based on the reservoir condition. The acid or alkaline will reduce the resistivity of the LoSal water while keeping its low salinity unchanged. The determination of the required volume of the acid or the alkaline is calculated using the conductivity mixing law and the solution is tested on core plugs. The possible effects of the acid on the formation lithology, specially the clay content is discussed and proved to be negligible due to the very low acid volume required. This is also supported by previously published measurements.
Telehealth has not previously been widely implemented as a result of regulatory and reimbursement concerns; however, in the current national emergency of the COVID-19 pandemic, the Centers for ...Medicare and Medicaid Services has relaxed many of its rules, allowing increased adoption of telehealth services, improving the safety and access of outpatient health care. A complete understanding of the regulatory requirements, technologic options, and billing processes of telehealth is required to initiate a successful clinic. A model is presented here based on a single institution's experience with implementing telehealth in the outpatient interventional radiology clinic.
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