Kidney cortex shear wave motion simulations based on segmented biopsy histology.

BACKGROUND AND OBJECTIVE: Biopsy stands as the gold standard for kidney transplant assessment, yet its invasive nature restricts frequent use. Shear wave elastography (SWE) is emerging as a promising alternative for kidney transplant monitoring. A parametric study involving 12 biopsy data sets categorized by standard biopsy scores (3 with normal histology, 3 with interstitial inflammation (i), 3 with interstitial fibrosis (ci), and 3 with tubular atrophy (ct)), was conducted to evaluate the interdependence between microstructural variations triggered by chronic allograft rejection and corresponding alterations in SWE measurements. METHODS: Heterogeneous shear wave motion simulations from segmented kidney cortex sections were performed employing the staggered-grid finite difference (SGFD) method. The SGFD method allows the mechanical properties to be defined on a pixel-basis for shear wave motion simulation. Segmentation techniques enabled the isolation of four histological constituents: glomeruli, tubules, interstitium, and fluid. Baseline ex vivo Kelvin-Voigt mechanical properties for each constituent were drawn from established literature. The parametric evaluation was then performed by altering the baseline values individually. Shear wave velocity dispersion curves were measured with the generalized Stockwell transform in conjunction with slant frequency-wavenumber analysis (GST-SFK) algorithm. By fitting the curve within the 100-400 Hz range to the Kelvin-Voigt model, the rheological parameters, shear elasticity (µ1) and viscosity (µ2), were estimated. A time-to-peak algorithm was used to estimate the group velocity. The resultant in silico models emulated the heterogeneity of kidney cortex within the shear wave speed (SWS) reconstructions. RESULTS: The presence of inflammation showed considerable spatial composition disparities compared to normal cases, featuring a 23 % increase in interstitial area and a 19 % increase in glomerular area. Concomitantly, there was a reduction of 12 % and 47 % in tubular and fluid areas, respectively. Consequently, mechanical changes induced by inflammation predominate in terms of rheological differentiation, evidenced by increased elasticity and viscosity. Mild tubular atrophy showed significant elevation in group velocity and µ1. Conversely, mild and moderate fibrosis exhibited negligible alterations across all parameters, compatible with relatively limited morphological impact. CONCLUSIONS: This proposed model holds promise in enabling patient-specific simulations of the kidney cortex, thus facilitating exploration into how pathologies altering cortical morphology correlates to modifications in SWE-derived rheological measurements. We demonstrated that inflammation caused substantial changes in measured mechanical properties.

Percutaneous Image Guided Cryoablation of Adrenal Metastases From Renal Cell Carcinoma: A Single Institution Review.

OBJECTIVES: To assess the safety, technical success, disease progression, and survival associated with percutaneous image-guided cryoablation of renal cell carcinoma metastasis (mRCC) in the adrenal gland. METHODS: Retrospective, single-institution review of adult patients undergoing percutaneous cryoablation for adrenal mRCC between the years of 2007-2021. Technical parameters, technical success, safety, and survival were analyzed according to standard criteria. RESULTS: Forty-six patients (39 male; mean age 66 ± 8.8 years) with 57 tumors ablated over 51 sessions with a median hospital length of stay of 1 day (range 0-3 days). Forty-four (96%) had primary of clear cell histology. Aim of ablation was curative intent in 39 of 57 tumors (72%) with local tumor control in the remainder. There were 2 (4%) technical failures and technique efficacy was achieved in 52 out of the remaining 55 (95%). There were no Common Terminology Criteria for Adverse Events' immediate complications and 4 of 51 (8%) delayed complications. Twenty-five of 57 (44%) had disease progression anywhere, away from ablation site. One-, 3-, and 5-year recurrence free survival rates were 100%, 89%, and 89% and overall survival was 98%, 85%, and 71%. Fifty-one of 57 (89%) underwent preprocedural alpha blockade with hypertensive crisis in 27 of 56 (54%) available records, of which there were no adverse outcomes. CONCLUSION: Percutaneous cryoablation of mRCC to the adrenal glands is safe with robust local control, leading to advocacy for its ongoing use in this patient population. Multi-disciplinary management is recommended for successful treatment.

Case series: The use of spermatic cord block in maximising patient comfort during ultrasound-guided percutaneous core-needle biopsy of the testicle.

Introduction/Purpose: Percutaneous core-needle biopsy of the testicle has been shown to be a safe and effective method of obtaining tissue for histological analysis and can be considered in specific clinical scenarios. While the use of spermatic cord block has been shown to be effective in pain relief in the emergent setting and as an anaesthetic option for inguinal surgery, its use in percutaneous core-needle biopsy has not been well described. Through this case series, we present our experience and technique of ultrasound-guided percutaneous core-needle biopsy using spermatic cord block in the setting of indeterminant testicular masses. Methods: Our departmental biopsy database was reviewed to identify patients who underwent percutaneous core-needle biopsy of the testicle from March 2010 to July 2022 and who also received spermatic cord block during the procedure. Results: Three patients were identified who met the search criteria. All three patients presented for the evaluation of indeterminant testicular mass and had a known non-testicular primary cancer diagnosis at the time of biopsy. All three biopsies were performed using a combination of spermatic cord block, moderate sedation, and local anaesthetic. Biopsies were obtained using an 18-gauge spring-loaded device with 4-5 core samples obtained during each procedure. All biopsies were well tolerated without significant pain or post-procedure complications. Discussion: Ultrasound-guided percutaneous core-needle testicular biopsy using spermatic cord block is a safe and effective option in sampling indeterminate testicular masses while maintaining patient comfort. Conclusion: The inclusion of a spermatic cord block in combination with local anaesthetic and moderate sedation has become standard practice in our institution, as we believe this maximises patient comfort and safety resulting in a better patient experience.

Morphometric analysis of tumor microvessels for detection of hepatocellular carcinoma using contrast-free ultrasound imaging: A feasibility study.

Introduction: A contrast-free ultrasound microvasculature imaging technique was evaluated in this study to determine whether extracting morphological features of the vascular networks in hepatic lesions can be beneficial in differentiating benign and malignant tumors (hepatocellular carcinoma (HCC) in particular). Methods: A total of 29 lesions from 22 patients were included in this work. A post-processing algorithm consisting of clutter filtering, denoising, and vessel enhancement steps was implemented on ultrasound data to visualize microvessel structures. These structures were then further characterized and quantified through additional image processing. A total of nine morphological metrics were examined to compare different groups of lesions. A two-sided Wilcoxon rank sum test was used for statistical analysis. Results: In the malignant versus benign comparison, six of the metrics manifested statistical significance. Comparing only HCC cases with the benign, only three of the metrics were significantly different. No statistically significant distinction was observed between different malignancies (HCC versus cholangiocarcinoma and metastatic adenocarcinoma) for any of the metrics. Discussion: Obtained results suggest that designing predictive models based on such morphological characteristics on a larger sample size may prove helpful in differentiating benign from malignant liver masses.

Hemodynamic course during ablation and selective hepatic artery embolization for metastatic liver carcinoid: a retrospective observational study.

BACKGROUND: Manipulation of carcinoid tumors during ablation or selective hepatic artery embolization (transarterial embolization, TAE) can release vasoactive mediators inducing hemodynamic instability. The main aim of our study was to review hemodynamics and complications related to minimally invasive treatments of liver carcinoids with TAE or ablation. METHODS: Electronic medical records of all patients with metastatic liver carcinoid undergoing ablation or TAE from 2003 to 2019 were abstracted. Noted were severe hypotension (mean arterial pressure [MAP] ..± 55.ßmmHg), severe hypertension (systolic blood pressure ... 180.ßmmHg), and perioperative complications. Associations of procedure type and pre-procedure octreotide use with intraprocedural hemodynamics were assessed using linear regression. A robust covariance approach using generalized estimating equation method was used to account for multiple observations. RESULTS: A total of 161 patients underwent 98 ablations and 207 TAEs. Severe hypertension was observed in 24 (24.5%) vs. 15 (7.3%), severe hypotension in 56 (57.1%) vs. 6 (2.9%), and cutaneous flushing observed in 2 (2.0%) vs. 48 (23.2%) ablations and TAEs, respectively. After adjusting for preprocedural MAP, ablation was associated with lower intraprocedural MAP compared to TAE (estimate -27.ßmmHg, 95%CI -30 to -24.ßmmHg, p.ß<.ß0.001). Intraprocedural declines in MAP were not affected by preprocedural use of octreotide (p.ß=.ß0.7 for TAE and p.ß=.ß0.4 for ablation). CONCLUSIONS: Ablation of liver carcinoids was associated with substantial hemodynamic instability, especially hypotension. In contrast, a higher number of TAE patients had cutaneous flushing. Preprocedural use of octreotide was not associated with attenuation of intraprocedural hypotension.

Hemodynamic course during ablation and selective hepatic artery embolization for metastatic liver carcinoid: a retrospective observational study

Abstract Background: Manipulation of carcinoid tumors during ablation or selective hepatic artery embolization (transarterial embolization, TAE) can release vasoactive mediators inducing hemodynamic instability. The main aim of our study was to review hemodynamics and complications related to minimally invasive treatments of liver carcinoids with TAE or ablation. Methods: Electronic medical records of all patients with metastatic liver carcinoid undergoing ablation or TAE from 2003 to 2019 were abstracted. Noted were severe hypotension (mean arterial pressure [MAP] ≤ 55 mmHg), severe hypertension (systolic blood pressure ≥ 180 mmHg), and perioperative complications. Associations of procedure type and pre-procedure octreotide use with intraprocedural hemodynamics were assessed using linear regression. A robust covariance approach using generalized estimating equation method was used to account for multiple observations. Results: A total of 161 patients underwent 98 ablations and 207 TAEs. Severe hypertension was observed in 24 (24.5%) vs. 15 (7.3%), severe hypotension in 56 (57.1%) vs. 6 (2.9%), and cutaneous flushing observed in 2 (2.0%) vs. 48 (23.2%) ablations and TAEs, respectively. After adjusting for preprocedural MAP, ablation was associated with lower intraprocedural MAP compared to TAE (estimate −27 mmHg, 95%CI −30 to −24 mmHg, p < 0.001). Intraprocedural declines in MAP were not affected by preprocedural use of octreotide (p = 0.7 for TAE and p = 0.4 for ablation). Conclusions: Ablation of liver carcinoids was associated with substantial hemodynamic instability, especially hypotension. In contrast, a higher number of TAE patients had cutaneous flushing. Preprocedural use of octreotide was not associated with attenuation of intraprocedural hypotension.

Innovative Fetal Therapy for a Giant Congenital Pulmonary Airway Malformation with Hydrops.

INTRODUCTION: Congenital pulmonary airway malformations (CPAMs) complicated by hydrops portend significant morbidity and mortality, with fetal survival estimates less than 10%. CASE PRESENTATION: We report successful use of ultrasound-guided radiofrequency ablation at 21-week gestation in a hydropic fetus with CPAM, with subsequent resolution of hydrops. Thirty-two-week MRI noted persistent mediastinal shift, and US at 36 weeks and 5 days noted polyhydramnios. Maternal gestational hypertension prompted delivery at 37 weeks, with a cesarean section performed after a failed trial of labor. The infant required CPAP at 100% and weaned to 21%. Tachypnea persisted, and chest CT on day of life 2 demonstrated multiple large cysts in the right lower lobe with anterior pneumothorax. On day of life 3, she successfully underwent a thoracoscopic right lower lobectomy. Adhesions to the chest wall and rib abnormalities were noted. She was extubated to CPAP at the conclusion of the procedure. She was able to wean to 21% on POD2 and transitioned to oral feeds. Her chest tube was removed with resultant ex vacuo pneumothorax noted. She remained asymptomatic and was discharged home on room air POD11. Pathology confirmed a type 1 CPAM. CONCLUSION: In utero radiofrequency ablation may be an adjunct to the management of large CPAM.

Feasibility and safety of percutaneous image-guided cryoablation of abdominal wall endometriosis.

PURPOSE: To evaluate the feasibility and safety of percutaneous image-guided cryoablation of abdominal wall endometriosis (AWE). MATERIALS AND METHODS: A retrospective review of percutaneous cryoablation (CT or MR) of AWE was performed from January 2018 to December 2020. Eighteen patients were identified from an internal percutaneous ablation database. Technical success, complications, and outcomes were analyzed according to standard nomenclature. RESULTS: Patients comprised 18 females (mean age 36.9 years) who underwent 18 cryoablation procedures to treat 23 AWE deposits. Three of the 18 cases were performed under MR guidance, while the remaining 15 employed CT guidance. Technical success was achieved in all 18 cases (100%). Fifteen of 18 patients (83%) had biopsy proven AWE deposits prior to treatment. Hydrodisplacement was used to displace adjacent bowel, bladder, or neurovascular structures in 13/18 cases (72%). The mean number of probes used per case was 3. Sixteen of 23 (70%) of AWE deposits had imaging follow-up (median 85 days). Of the 16 lesions with imaging follow-up, 15 (94%) demonstrated no residual enhancement or T1 hyperintensity at the treatment site and 1 lesion (6%) demonstrated residual/progressive disease. At clinical follow-up, 13 of 14 (93%) patients reported improvement in AWE-related symptoms. Eleven patients had clinically documented pain scores before and after ablation and all demonstrated substantial symptomatic improvement. No society of interventional radiology (SIR) major complications were observed. CONCLUSIONS: Percutaneous cryoablation of AWE is feasible with a favorable safety profile. Further longitudinal studies are needed to document durable response over time.

A Clinical Decision Aid to Support Personalized Treatment Selection for Patients with Clinical T1 Renal Masses: Results from a Multi-institutional Competing-risks Analysis.

BACKGROUND: Personalized treatment for clinical T1 renal cortical masses (RCMs) should take into account competing risks related to tumor and patient characteristics. OBJECTIVE: To develop treatment-specific prediction models for cancer-specific mortality (CSM), other-cause mortality (OCM), and 90-d Clavien grade ≥3 complications across radical nephrectomy (RN), partial nephrectomy (PN), thermal ablation (TA), and active surveillance (AS). DESIGN, SETTING, AND PARTICIPANTS: Pretreatment clinical and radiological features were collected for consecutive adult patients treated with initial RN, PN, TA, or AS for RCMs at four high-volume referral centers (2000-2019). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Prediction models used competing-risks regression for CSM and OCM and logistic regression for 90-d Clavien grade ≥3 complications. Performance was assessed using bootstrap validation. RESULTS AND LIMITATIONS: The cohort comprised 5300 patients treated with RN (n = 1277), PN (n = 2967), TA (n = 476), or AS (n = 580). Over median follow-up of 5.2 yr (interquartile range 2.5-8.7), there were 117 CSM, 607 OCM, and 198 complication events. The C index for the predictive models was 0.80 for CSM, 0.77 for OCM, and 0.64 for complications. Predictions from the fitted models are provided in an online calculator (https://small-renal-mass-risk-calculator.fredhutch.org). To illustrate, a hypothetical 74-yr-old male with a 4.5-cm RCM, body mass index of 32 kg/m2, estimated glomerular filtration rate of 50 ml/min, Eastern Cooperative Oncology Group performance status of 3, and Charlson comorbidity index of 3 has predicted 5-yr CSM of 2.9-5.6% across treatments, but 5-yr OCM of 29% and risk of 90-d Clavien grade 3-5 complications of 1.9% for RN, 5.8% for PN, and 3.6% for TA. Limitations include selection bias, heterogeneity in practice across treatment sites and the study time period, and lack of control for surgeon/hospital volume. CONCLUSIONS: We present a risk calculator incorporating pretreatment features to estimate treatment-specific competing risks of mortality and complications for use during shared decision-making and personalized treatment selection for RCMs. PATIENT SUMMARY: We present a risk calculator that generates personalized estimates of the risks of death from cancer or other causes and of complications for surgical, ablation, and surveillance treatment options for patients with stage 1 kidney tumors.

Safety and Efficacy of Percutaneous Image-Guided Mediastinal Mass Core-Needle Biopsy.

OBJECTIVE: To retrospectively evaluate the safety and efficacy of percutaneous image-guided mediastinal mass core-needle biopsy. PATIENTS AND METHODS: Retrospective review of an institutionally maintained biopsy registry identified 337 computed tomography- or ultrasound-guided percutaneous mediastinal mass core needle biopsies between October 2002 and August 2017 in a single quaternary referral center. Mean patient age was 51 (range, 18 to 93) years. Procedural techniques, anticoagulation/antiplatelet therapy, and tumor anatomical characteristics were reviewed. Classification and gradation of complications was based on the Clavien-Dindo system. Diagnostic yield was defined as the ratio of diagnostic biopsy to all biopsies performed. RESULTS: Mean tumor size was 59.2 (range, 10 to 180) mm with 89.9% (n=303) of lesions located in the prevascular (anterior) mediastinum. There was a single major complication (0.3%) of a symptomatic pneumothorax requiring intervention. There were seven (2.1%) minor complications, including three bleeding complications. A transpleural approach was the only variable associated with an increased complication rate (P<.01). Forty-one (12.2%) patients had a biopsy performed while taking an antiplatelet/anticoagulant agent within the therapeutic window, with a single case (0.3%) associated with a minor bleeding complication. Of 18 (5.3%) procedures performed without cessation of anticoagulant/antiplatelet therapy, there were no bleeding complications. Of all 337 biopsies, 322 (95.5%) were diagnostic. None of the analyzed variables were significantly associated with a nondiagnostic biopsy. CONCLUSION: Image-guided percutaneous core-needle biopsy of mediastinal masses is a safe procedure with high diagnostic yield. Further prospective studies are required to assess the complication profile in higher risk patients.

Novel Uses of Ultrasound to Assess Kidney Mechanical Properties.

Ultrasound is a key imaging tool for evaluating the kidney. Over the last two decades, methods to measure the mechanical properties of soft tissues have been developed and used in clinical practice, although use in the kidney has not been as widespread as for other applications. The mechanical properties of the kidney are determined by the structure and composition of the renal parenchyma and perfusion characteristics. Because pathologic processes change these factors, the mechanical properties change and can be used for diagnostic purposes and for monitoring treatment or disease progression. Ultrasound-based elastography methods for evaluating the mechanical properties of the kidney use focused ultrasound beams to perturb the kidney and then high frame-rate ultrasound methods are used to measure the resulting motion. The motion is analyzed to estimate the mechanical properties. This review will describe the principles of these methods and discuss several seminal studies related to characterizing the kidney. Additionally, an overview of the clinical use of elastography methods in native and kidney allografts will be provided. Perspectives on future developments and uses of elastography technology along with other complementary ultrasound imaging modalities will be provided.

Long-term renal function outcomes after renal cryoablation complicated by major hemorrhage requiring selective transarterial embolization.

PURPOSE: To determine long-term renal function outcomes after renal cryoablation complicated by major hemorrhage requiring transarterial embolization compared to patients who underwent uncomplicated renal cryoablation without major hemorrhage. METHODS: Utilizing a matched cohort study design, retrospective review identified 23 patients who underwent percutaneous image-guided renal cryoablation complicated by major hemorrhage requiring ipsilateral transarterial embolization (TAE group) and a control group of 23 patients who underwent uncomplicated renal cryoablation matched 1:1 by age, gender and RENAL Nephrometry score at a single institution from 1/1/2005 to 12/31/2019. Primary outcome parameters included change in creatinine (mg/dl) and estimated glomerular filtration rate (ml/min/1.73 m2; eGFR) from baseline and were compared between TAE and control group using a paired t-test. RESULTS: There was a significantly higher proportion of patients on pre-ablation anticoagulation in the TAE v. control group (30% v. 4%; p = 0.047), but all patients were off anticoagulation and with normal coagulation parameters at the time of cryoablation. Otherwise there were no significant differences in clinical, renal tumor, Charlson co-morbidity index, baseline renal function or cryoablation parameters between the TAE and control group. In the post-ablation period, there was trend toward greater increase in creatinine from baseline to worst post-ablation creatinine in the TAE v. the control group (+ 0.5 ± 0.7 mg/dl v. 0.2 ± 0.1 mg/dl; p = 0.056). However, at a mean follow-up of 42.7 ± 35.7 months, there was no significant difference between the TAE and control group in creatinine (p = 0.68), eGFR (p = 0.60) or change from baseline in creatinine (p = 0.28), eGFR (p = 0.80) or CKD stage (p = 0.74). No patient required initiation of hemodialysis. CONCLUSION: Selective transarterial embolization for post-renal cryoablation hemorrhage does not significantly affect long-term renal function compared to cryoablation alone. Pre-ablation anticoagulation despite normal coagulation at time of ablation may be a risk factor for post-ablation hemorrhage, and warrants further evaluation when considering pre-ablation embolization.

Percutaneous Image-Guided Thermal Ablation of Adrenal Metastasis from Melanoma: A Single-Institution Experience.

The outcomes of technically successful image-guided percutaneous thermal ablation of melanoma adrenal metastases involving 11 tumors in 9 consecutive patients over 12 years (2009-2020) were evaluated. All patients had multiple treated metastatic sites, and 44.4% (4/9) had greater than 5 metastatic sites. The mean maximal tumor diameter was 3.6 ± 1.6 cm. The local recurrence-free survival at 1 year was 85.7%. With a median survival of 19.4 months, 66.6% (6/9) of patients died from tumor progression. The 1- and 3-year overall survival rate was 60.0% and 30.0%, respectively. All patients were pretreated with alpha-adrenergic blockade, and 36% (4/11) developed a hypertensive crisis. The median hospital length of stay was 1 day (range, 1-2 days), without any major complications. Thermal ablation of adrenal metastasis from a melanoma provides acceptable local control and a good safety profile.

Preservation of Renal Function after Major Bleeding Events due to Ultrasound-Guided Parenchymal Renal Biopsy.

The clinical outcomes of major bleeding events following ultrasound-guided native and allograft parenchymal renal biopsy were evaluated. Forty-eight bleeding complications after biopsy (Society of Interventional Radiology adverse event grade ≥ 2) from 2002 to 2018 were identified. The primary outcome assessed was renal function. The clinical outcomes and interventions performed, including blood transfusion, angiography with or without embolization, nephrostomy tube placement, surgery, nephrectomy, hospitalization, intensive care unit admission, dialysis, and survival, were noted. Renal function may be moderately diminished in the short-term periprocedural setting. None of the patients studied died or required nephrectomy or the initiation of dialysis as a result of a major bleeding complication after the renal biopsy.

A Single-Institution Experience in Percutaneous Image-Guided Cryoablation of Lymph Node Metastases.

OBJECTIVE. The purpose of this study was to assess the feasibility, safety, and efficacy of percutaneous cryoablation for the treatment of lymph node metastases. MATERIALS AND METHODS. In this single-institution retrospective study 55 patients were identified who underwent CT-guided cryoablation of metastatic lymph nodes between November 2006 and September 2019. Patient demographics, disease characteristics, and procedural details were recorded. The primary endpoints were technical success and major complications. The secondary endpoints were time to local and time to distant progression. Complications were graded according to the Society of Interventional Radiology consensus guidelines. RESULTS. The study sample comprised 55 patients (42 men, 13 women; mean age 64 ± 12 years) who underwent 61 cryoablation procedures to treat 65 lymph node metastases. Targeted nodes measured 1.7 ± 1.2 cm in mean short-axis diameter. Technical success was achieved in 60 of 61 cryoablation procedures (98%). Adjunctive maneuvers performed to protect adjacent structures included hydrodissection (n = 40), ureteral stenting (n = 3), and neural monitoring (n = 3). There were two Society of Interventional Radiology major complications (3%): pneumothorax (n = 1) and bleeding (n = 1). Local tumor control was achieved in treatment of 53 of 65 (82%) nodal metastases within a median of 25 months (range, 1-121 months) of follow-up. Local progression occurred in 12 of 65 cases (18%); the median time to recurrence was 11 months. CONCLUSION. Percutaneous cryoablation of nodal metastases is feasible and safe. Further investigation is warranted to assess the long-term efficacy of this technique and to define its role in oncologic care.

Percutaneous Image-Guided Core Needle Biopsy of Neuroendocrine Tumors: How Common Is Intraprocedural Carcinoid Crisis?

PURPOSE: To retrospectively evaluate the incidence of carcinoid crisis, other complications, and physiologic disturbances during percutaneous image-guided core needle biopsy of neuroendocrine tumors (NETs) in the lung and the liver. MATERIALS AND METHODS: Between January 2010 and January 2020, 106 computed tomography (CT) or ultrasound (US)-guided core needle biopsies of lung and liver NETs were performed in 95 consecutive adult patients. The mean age was 64 ± 13 years, and 48% were female. The small bowel was the most common primary site (33%, 31/95), and 32 (34%) patients had pre-existing symptoms of carcinoid syndrome. The mean tumor size was 3.2 ± 2.6 cm, and mean number of passes was 3.4 ± 1.6. A 17/18-gauge needle was used in 91% (96/106) of the biopsies. Thirteen (12%) patients received either outpatient or prophylactic octreotide. RESULTS: No patients experienced carcinoid crisis or needed octreotide, inotropes, vasopressors, or resuscitation. A single biopsy procedure (0.9%, 1/106) was complicated by bleeding that required angiographic hepatic artery embolization. Changes in pre-biopsy- versus post-biopsy systolic blood pressure and heart rate were -1.6 mm Hg (P = .390) and 0.6 beat/min (P = .431), respectively. Tumor functional status, overall tumor burden, and the elevation of neuroendocrine markers were not associated with intraprocedural physiologic disturbances. There were 4 minor complications (0.4%, 4/106) associated with the biopsy procedure that were not attributed to hormone excretion from tumor manipulation. CONCLUSIONS: Percutaneous image-guided core biopsy of NETs is safe, with low complication rate and no definite carcinoid crisis in the current cohort.

Detection of distal ureteral stones in pregnancy using transvaginal ultrasound.

AIMS: To determine the performance of transvaginal ultrasound for the visualization of distal ureteral stones in pregnant patients with renal colic and to evaluate the diagnostic value of secondary findings suggestive of obstructing ureteral stone disease. METHODS: We retrospectively identified 129 pregnant patients with a total of 142 encounters with both abdominal and transvaginal ultrasound. Ultrasound images for each patient were reviewed recording the presence of stone with location, hydronephrosis, resistive indices (RI), and status of the ureteral jets. Patients were subcategorized into two groups based on the visualization of distal ureteral stone. RESULTS: The transvaginal technique identified 94% (N = 16/17) of sonographically detected stones in the distal ureter/urethra, while the transabdominal technique identified 29% (N = 5/17). The combined imaging for initial assessment of renal colic in pregnancy demonstrated a sensitivity of 89%, specificity 100%, and negative predictive value (NPV) of 98%. The frequency of hydronephrosis was statistically greater in the visualized stone group (94% vs 51%). Mean RI was identical in both groups however the delta RI was significantly elevated in those patients with distal ureteral stones with a mean delta RI value of 0.05. The rate of absence of ureteral jets was not statistically significant. CONCLUSION: The present data would suggest a utility of transvaginal ultrasound for the evaluation of the pregnant patient with 94% of distal stones being detected transvaginal versus 29% transabdominally. Additionally, there was significantly increased hydronephrosis and elevated RIs in patients with distal ureteral stones.