Patient and Provider Perspectives of Telehealth and In-Person Interventional Radiology Clinic Visits

PurposeTo assess patient and provider satisfaction with interventional radiology (IR) outpatient telehealth and in-person clinic.Materials and MethodsThis institutional review board–approved study analyzed patient satisfaction with clinic via survey after an IR outpatient telehealth or in-person visit. A physician telehealth experience survey was completed by 8 IR physicians.ResultsDuring the initial survey period, 44 (83%) of 53 patients completed a survey via telephone compared with 37 (23%) of 158 patients who were offered an electronic survey during the second survey period. Of 81 respondents, 18 (22%) were in-person and 63 (78%) were via telehealth. Of the respondents, nearly all patients (97%) in the telehealth group reported satisfaction with their telehealth clinic visit, with similar rates of high patient satisfaction between in-person and telehealth visits (P = .51). Most patients (98%) in the telehealth group strongly agreed that their physician’s recommendations were clear in the telehealth visit and that their visit was private, similar to in-person visits (P = .13). A telehealth visit saved time for all patients (100%), with 78% reporting >1 hour of time-saving. All IR physicians (n = 8) reported greater efficiency with telehealth clinic than with in-person clinic and that follow-up patterns would change if telehealth was available. However, all providers (100%) found telephone visits less satisfying than in-person visits, with video visits being either equally satisfying (71%) or less satisfying (29%).ConclusionsPatient satisfaction with the in-person and telehealth outpatient IR clinic was high, with patients and providers reporting time-saving and greater efficiency with telehealth, suggesting that telehealth should remain an important component of outpatient IR clinic care.     

Inflammation burst after 5-aminolevulinic acid-photodynamic therapy for the treatment of actinic keratosis complicating rosacea: A case report

A 72-year-old woman suffering from multiple actinic keratosis (AK) complicating steroid-induced rosacea received 5-aminolevulinic acid-photodynamic therapy (ALA-PDT) in our outpatient clinic. Both AKs and rosacea achieved remission after one session of PDT. However, an adverse effect of severe acute inflammatory response emerged with lasting hyperpigmentation. We then terminated the following PDT sessions . After skin care and close follow-up for a half year, most symptoms and lesions of AK and rosacea disappeared with mild hyperpigmentation left. ALA-PDT is commonly recommended for multiple AKs based on effectiveness and noninvasiveness, but has controversial efficacy and safety for rosacea. The unusual excessive inflammation in this patient after ALA-PDT may due to skin barrier destruction, vasomotor dysfunction and the immune response by dead Demodex after PDT. This case indicated that carefully evaluation before ALA-PDT is of great importance, especially for those patients with complicated skin situation. For AKs complicating rosacea, modified parameters of ALA-PDT such as less ALA incubation time or reduced light dose should be further studied to achieve the optimal efficacy and safety of ALA-PDT and offer the best benefit.     

Outcomes of Hemorrhoidal Artery Embolization from a Multidisciplinary Outpatient Interventional Center

PurposeTo evaluate the safety and efficacy of outpatient transarterial embolization for symptomatic refractory internal hemorrhoids.Materials and MethodsRetrospective analysis of 134 patients who underwent hemorrhoidal artery embolization (HAE) for symptomatic internal hemorrhoids between August 2021 and June 2022 (76 men and 58 women) was performed. The mean age was 54.9 years, with a mean Goligher hemorrhoid grade (HG) of 2.1. Branches of the superior rectal artery (SRA) or middle rectal artery supplying the corpus cavernosum recti were embolized with both spherical particles and microcoils. Standard-of-care evaluations were performed at baseline and the 1 month follow-up, which included hemorrhoid-related pain (HRP) (0–10), hemorrhoid symptoms score (HSS) (5–20), quality of life (QoL) (0–4), French bleeding score (FBS) (0–9), and HG (0–4). Clinical success was defined as improvement of symptoms without additional treatment.ResultsEmbolization of at least 1 hemorrhoidal artery was achieved in 133 (99%) of the 134 patients. The mean number of SRA branches embolized per patient was 2.9 ± 1.0. Clinical success was seen in 93% (124 of 134) of patients at the 1-month follow-up, with 10 patients requiring repeat embolization. There were significant improvements in all mean outcomes at 1 month: HSS (11–7.8; P < .01), HRP (4.1–1.3; P < .01), QoL (2.2–0.8; P < .01), FBS (4.4–2.2; P < .01), and HG (2.3–1.2; P < .05). There were no severe adverse events.ConclusionsHAE is a safe and effective outpatient treatment for refractory symptomatic internal hemorrhoids in the short term.     

Utilization of Endovascular and Surgical Treatments for Symptomatic Uterine Leiomyomas: A Population Health Perspective

PurposeTo conduct a population-level analysis of surgical and endovascular interventions for symptomatic uterine leiomyomata by using administrative data from outpatient medical encounters.Materials and MethodsBy using administrative data from all outpatient hospital encounters in California (2005–2011) and Florida (2005–2014), all patients in the outpatient setting with symptomatic uterine leiomyomata were identified. Patients were categorized as undergoing hysterectomy, myomectomy, uterine artery embolization (UAE), or no intervention. Hospital stay durations and costs were recorded for each encounter.ResultsA total of 227,489 patients with uterine leiomyomata were included, among whom 39.9% (n = 90,800) underwent an intervention, including hysterectomy (73%), myomectomy (19%), or UAE (8%). The proportion of patients undergoing hysterectomy increased over time (2005, hysterectomy, 53.2%; myomectomy, 26.9%; UAE, 18.0%; vs 2013, hysterectomy, 80.1%; myomectomy, 14.4%; UAE, 4.0%). Hysterectomy was eventually performed in 3.5% of patients who underwent UAE and 4.1% who underwent myomectomy. Mean length of stay following hysterectomy was significantly longer (0.5 d) vs myomectomy (0.2 d) and UAE (0.3 d; P < .001 for both). The mean encounter cost for UAE ($3,772) was significantly less than those for hysterectomy ($5,409; P < .001) and myomectomy ($6,318; P < .001). Of the 7,189 patients who underwent UAE during the study period, 3.5% underwent subsequent hysterectomy.ConclusionsThe proportion of women treated with hysterectomy in the outpatient setting has increased since 2005. As a lower-cost alternative with a low rate of conversion to hysterectomy, UAE may be an underutilized treatment option for patients with uterine leiomyomata.     

Results of an American College of Radiology-Society of Interventional Radiology Membership Survey on Exclusive Contracts and the Attitudes of Interventional Radiologists

PurposeTo assess the attitudes of interventional radiologists (IRs) and diagnostic radiologists (DRs) toward exclusive contracts and independently practicing IRs who may request privileges at a hospital where an exclusive contract exists with a different group of radiologists.Materials and MethodsA total of 22,400 survey instruments were distributed to 4,490 IRs and 17,910 DRs in the United States. Statistical evaluation included multivariate ordinal logistic regression analysis with calculation of the odds ratios and forest plots.ResultsCompleted surveys were received from 525 (11.69%) IRs and 401 (2.23%) DRs. Given the low response rate of DRs, data analysis was focused on IRs. Early-career IRs and those in outpatient practices had a more positive attitude toward independent IRs who requested admitting and/or procedural privileges. A supermajority of both IRs and DRs who responded to the survey agreed that the importance of IR to hospital and health system contracts will increase.ConclusionsThis survey identified many interrelated and complex variables that significantly affected the attitudes of IRs in various practice settings toward independent IRs requesting hospital admitting and/or procedural privileges. It will benefit independent IRs seeking admitting privileges to better understand some of the factors that impact the potential willingness of the radiology groups and other IRs with exclusive hospital contracts to work toward mutually beneficial practice paradigms, especially as more clinically oriented IRs complete their training in the new, integrated residency programs.     

Outpatient Percutaneous Endovascular Abdominal Aortic Aneurysm Repair: A Single-Center Experience

PurposeTo evaluate the safety of outpatient percutaneous endovascular abdominal aortic repair (PEVAR) versus inpatient PEVAR without or with adjunct procedures.Materials and MethodsBetween January 2012 and June 2019, a cohort of 359 patients comprising 168 (46.8%) outpatients and 191 (53.2%) inpatients who had undergone PEVAR were enrolled. All the patients were asymptomatic but had indications for endovascular aortic repair, ie, fit for intravenous anesthesia and anatomically feasible with standard devices. Patient sex, age, comorbidities, smoking status, type of anesthesia, adjunct procedures, type of graft device, operative times, mortality, complications, and readmissions were analyzed.ResultsMedian follow-up period was 16.5 months (interquartile range, 9–31 months). Except for a higher percentage of tobacco use (42.6% vs 28.8%; P = .04), dyslipidemia (39.7% vs 19.2%; P < .01), and use of local anesthesia (99.4% vs 82.2%; P < .01) in the outpatients, there was no significant difference in the type of graft and adjunct procedures used. No outpatient mortality occurred. There was no difference in the number, severity, and onset of complications (all P > .05). Outpatient unexpected same-day admission, 30-day readmission, and emergency department visit rates were 4.8%, 2.4% (P = .13), and 10% (P < .01), respectively. Operative times for outpatient PEVAR without adjunct procedures were shorter (P < .01).ConclusionsOutpatient PEVAR can be performed with a safety profile similar to that of inpatient PEVAR. The unexpected same-day admission, 30-day readmission, and emergency department visit rates were low. The outpatient PEVARs without adjunct procedures took less time.     

High-Suspicion Subcentimeter Thyroid Nodules: Cost Effectiveness of Active Surveillance versus Fine Needle Aspiration

PurposeTo compare the cost-benefit of active surveillance (AS) against immediate fine needle aspiration (FNA) of sonographically suspicious subcentimeter thyroid nodules.Materials and MethodsA Markov model was constructed to compare the cost-benefit of 3 strategies from the point of discovery until death: (a) Surveillance of all nodules, (b) Surveillance of nodules with positive cytology, and (c) Surgery of nodules with positive cytology. The reference case was a 40-year-old woman with a sonographically suspicious subcentimeter thyroid nodule. Transition probabilities, costs, and health state utilities were derived from the literature. Sensitivity analyses were performed to evaluate model uncertainty. Willingness-to-pay threshold was set at $100,000/quality-adjusted life year.ResultsSurveillance of nodules with positive cytology dominated in the reference scenario and was cost-beneficial over Surveillance of all nodules, independent of the utility of AS. Surveillance of all nodules was cost-beneficial only at a life expectancy of <2.6 years or surveillance duration of <4 years.ConclusionsWhile current guidelines recommend AS of sonographically suspicious subcentimeter nodules, the results of this study suggest that immediate FNA (Surveillance of nodules with positive cytology) is more cost-beneficial than AS (Surveillance of all nodules). Patients with positive cytology on FNA may subsequently opt for AS (Surveillance of nodules with positive cytology) or surgery (Surgery of nodules with positive cytology) according to their level of comfort (ie, utility) with AS.     

Robot-Assisted Transarterial Chemoembolization of Hepatocellular Carcinoma Using a Coaxial Microcatheter Driving Controller-Responder Robot System: Clinical Pilot Study

PurposeTo evaluate the feasibility and safety of robot-assisted transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) using a new coaxial microcatheter driving controller-responder robot (CRR) system.Materials and MethodsA single-center prospective pilot study approved by the institutional review board was conducted using this CRR developed after analyzing 20 cases of conventional TACE procedures from May to October 2021. The study included 10 patients with HCCs: 5 (median age, 72 years; range, 64–73 years) underwent robot-assisted TACE, and 5 (median age, 57 years; range, 44–76 years) underwent conventional TACE for comparison. The feasibility and safety of robot-assisted TACE were evaluated by assessing the technical success, procedure time, adverse event rate, radiation dose, and early tumor response.ResultsThe entire TACE procedure was divided into 30 steps, of which 8 could be robotized. In robot-assisted TACE, technical success was achieved in 4 (80%) of 5 patients. No procedure-related adverse event was observed. The median procedure time was 56 minutes. At the 1-month follow-up, 3 of the 4 patients showed a complete or partial response after robot-assisted TACE. The median radiation doses for the operator and patients were 0.4 and 2,167.5 μSv in robot-assisted TACE and 53.2 and 2,989.7 μSv in conventional TACE, respectively.ConclusionsRobot-assisted TACE using a new CRR system was feasible and safe for the treatment of HCC and could remarkably decrease radiation exposure for the operators.     

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

PurposeTo 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 MethodsBetween 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.ResultsNo 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.ConclusionsPercutaneous image-guided core biopsy of NETs is safe, with low complication rate and no definite carcinoid crisis in the current cohort.     

Technical Considerations and Clinical Outcomes in the Endovascular Management of Celiac Arterial Aneurysms

This retrospective case series details a single-center experience of 8 patients (mean age, 54.4 years) with celiac artery aneurysms (CAAs) who underwent 1 parent vessel-sparing, 5 partial parent vessel-sparing, and 2 non-parent vessel-sparing procedures. Technical success was achieved in 6 of 8 (75%) patients. Both technical failures arose from type II endoleaks, which spontaneously resolved, resulting in clinical success of all cases. In-stent restenosis requiring reintervention complicated 3 of 5 (60%) partial parent vessel-sparing techniques, with 2 of 3 developing complete thrombosis. Two Society of Interventional Radiology grade C complications were recorded, none of which resulted in permanent sequelae. The endovascular management of CAAs is safe and amenable to various techniques.     

Changes in the National Endovascular Management of Femoropopliteal Arterial Disease: An Analysis of the 2011–2019 Medicare Data

PurposeTo describe national trends in the utilization of endovascular approaches (including balloon angioplasty, atherectomy, and stent placement) for the management of femoropopliteal peripheral arterial disease (PAD).Materials and MethodsThe Medicare Physician/Supplier Procedure Summary dataset containing 100% of Part B claims was interrogated for years 2011–2019. The Current Procedural Terminology codes specific for femoropopliteal angioplasty, stent placement, and atherectomy were used to create summary statistics for utilization by year, place of service (hospital inpatient, hospital outpatient, and office-based laboratory), and provider specialty (cardiology, radiology, and surgery).ResultsThe use of atherectomy increased from 34,732 (33%) procedures in 2011 to 75,435 (53%) procedures in 2019, and atherectomy became the dominant treatment strategy for femoropopliteal PAD. The relative utilization of stent placement (36,793 [35%] to 28,899 [20%]) and angioplasty only (34,398 [32%] to 38,228 [27%]) decreased concomitantly from 2011 to 2019. By 2019, the use of atherectomy was twofold higher in office-based laboratories than in the outpatient hospital setting (44,767 and 20,901, respectively). Treatment strategy varied by provider specialty in 2011 when cardiologists used atherectomy most frequently (17,925 [43%]), whereas radiologists used angioplasty alone (5,928 [6%]) and surgeons stented (18,009 [37%]) most frequently. By 2019, all specialties utilized atherectomy most frequently (29,564 [59%] for cardiology, 10,912 [58%] radiology, and 33,649 [47%] surgery).ConclusionsThe national approach to endovascular management of femoropopliteal PAD has changed since 2011 toward an implant-free strategy, including a multifold increase in the use of atherectomy. Discordant rates of atherectomy use between the ambulatory hospital and office-based settings highlight the need for comparative effectiveness studies to guide management.     

Reimagining the IR Workflow for a Better Work–Life Balance

Several workflow changes were implemented in a large academic interventional radiology practice, including separation of inpatient and outpatient services, early start times, and using an adaptive learning system to predict case length tailored to individual physicians. Metrics including procedural volume, on-time start, accuracy at predicting case length, and room shutdown time were assessed before and after the intervention. Considerable improvements were seen in accuracy of first case start times, predicting block times, and last case encounter ending times. It is proposed that with improved role clarity, interventional radiologists can regain control over their schedules, utilize work hours more efficiently, and improve work–life balance.     

Endovascular Assessment of Liver Hemodynamics in Patients with Cirrhosis Complicated by Portal Hypertension

The hepatic venous pressure gradient (HVPG) is currently considered the gold standard to assess portal hypertension (PH) in patients with cirrhosis. A meticulous technique is important to achieve accurate and reproducible results, and values obtained during measurement are applied in risk stratification of patients with PH, allocating treatment options, monitoring follow-up, and deciding management options in surgical patients. The use of portosystemic pressure gradients in patients undergoing placement of transjugular intrahepatic portosystemic shunts has been studied extensively and has great influence on decisions on shunt diameter. The purpose of this study was to describe the recommended technique to measure HVPG and portosystemic pressure gradient and to review the existing literature describing the importance of these hemodynamic measurements in clinical practice.     

Intraprocedural Superior Hypogastric Nerve Block Allows Same-Day Discharge following Uterine Artery Embolization

In a single-arm, nonrandomized, retrospective case-control study, 39 patients (mean age, 44 y) who underwent elective outpatient uterine artery embolization with the use of superior hypogastric nerve block (SNHB) for pain control over a period of 3 years were identified. Technical success of SNHB was 87%. Of the 34 patients who received SNHB, 97% did not need a patient-controlled analgesia pump. The median opioid requirement for the 17 patients who needed opioid agents was 7.5 morphine milligram equivalents (interquartile range [IQR], 10). The median length of stay was 2.2 hours (IQR, 1.7 h). SHNB offers a safe and effective intervention that significantly reduces pain and the need for opiate agents and allows same-day discharge after uterine artery embolization.     

Impact of the Ablative Margin on Local Tumor Progression after Radiofrequency Ablation for Lung Metastases from Colorectal Carcinoma: Supplementary Analysis of a Phase II Trial (MLCSG-0802)

PurposeTo explore what extent of ablative margin depicted by computed tomography (CT) immediately after radiofrequency (RF) ablation is required to reduce local tumor progression (LTP) for colorectal cancer (CRC) lung metastases.Materials and MethodsThis retrospective study was undertaken as a supplementary analysis of a previous prospective trial. Seventy patients (49 men and 21 women; mean age ± standard deviation, 64.9 years ± 10.6 years) underwent RF ablation for CRC lung metastases, and 95 tumors that were treated in the trial and followed up with CT at least 12 months after RF ablation were evaluated. The mean tumor size was 1.0 cm ± 0.5 cm. The ablative margin was estimated as the shortest distance between the outer edge of the tumor and the surrounding ground-glass opacity on CT obtained immediately after RF ablation. The impact of the ablative margin on LTP was evaluated using logistic regression analysis. Multivariate logistic regression analysis was also performed to identify the risk factors for LTP. The result was validated with multivariate logistic regression applying a bootstrap method (1,000 times resampling).ResultsThe mean ablative margin was 2.7 mm ± 1.3 (range, 0.4–7.3 mm). LTP developed in 6 tumors (6%, 6/95) 6–19 months after RF ablation. The LTP rate was significantly higher when the margin was less than 2 mm (P = .023). A margin of <2 mm was also found to be a significant factor for LTP (P = .048) on multivariate analysis and validated using the bootstrap method (P = .025).ConclusionsAn ablative margin of at least 2 mm is important to reduce LTP after RF ablation for CRC lung metastases.     

Transjugular Intrahepatic Portosystemic Shunts Reduce Variceal Bleeding and Improve Survival in Patients with Cirrhosis: A Population-Based Analysis

PurposeTo investigate from a population health perspective the effects of transjugular intrahepatic portosystemic shunt (TIPS) creation on recurrent variceal bleeding and survival in patients with cirrhosis.Materials and MethodsPatients with cirrhosis who presented to outpatient and acute-care hospitals in California (2005–2011) and Florida (2005–2014) with variceal bleeding comprised the study cohort. Patients entered the study cohort at their first presentation for variceal bleeding; all subsequent hospital encounters were then evaluated to determine subsequent interventions, complications, and mortality data.ResultsA total of 655,577 patients with cirrhosis were identified, of whom 42,708 (6.5%) had at least 1 episode of variceal bleeding and comprised the study cohort. The median follow-up time was 2.61 years. A TIPS was created in 4,201 (9.8%) of these patients. There were significantly greater incidences of coagulopathy (83.9% vs 72.8%; P < .001), diabetes (45.5% vs 38.8%; P < .001), and hepatorenal syndrome (15.3% vs 12.5%; P < .001) in TIPS recipients vs those without a TIPS. Following propensity-score matching, TIPS recipients were found to have improved overall survival (82% vs 77% at 12 mo; P < .001) and a lower rate of recurrent variceal bleeding (88% vs 83% recurrent bleeding–free survival at 12 months,; P < .001) than patients without a TIPS. Patients with a TIPS had a significant increase in encounters for hepatic encephalopathy vs those without (1.01 vs 0.49 per year; P < .001).ConclusionsTIPS improves recurrent variceal bleeding rates and survival in patients with cirrhosis complicated by variceal bleeding. However, TIPS creation is also associated with a significant increase in hepatic encephalopathy.     

Computed Tomography Fluoroscopy–Guided Percutaneous Transhepatic Bleomycin/Ethiodized Oil Sclerotherapy for Symptomatic Giant Hepatic Hemangioma

PurposeTo determine the safety and efficacy of computed tomography (CT) fluoroscopy–guided percutaneous transhepatic sclerotherapy with a bleomycin/ethiodized oil emulsion for symptomatic giant hepatic hemangiomas.Materials and MethodsThe procedure was performed on 22 patients with symptomatic giant hepatic hemangiomas in an outpatient setting between 2018 and 2020. All patients were followed clinically and underwent contrast-enhanced magnetic resonance imaging after 1 month and again at a mean time of 15 months ± 2. Adverse events were classified according to the Common Terminology Criteria for Adverse Events (CTCAE, v5.0), in which a severe adverse event was defined as an adverse event with a grade of ≥3. The desired radiologic response (volume and index size) and improvement of pain intensity (visual analog scale [VAS]) and other symptoms were recorded as outcomes.ResultsOverall, patients showed a 36.4% ± 8.6 reduction in volume and a 14% ± 1.6 reduction in index size after 1 month, with P values of .002 and .001, respectively. The final follow-up volume and index size were 194.7 cm³ ± 25.8 and 77 mm ± 36, respectively. Moreover, a 53.0% ± 7 reduction in volume and 22% ± 3.7 reduction in index size during the final imaging were reported, with the P values of .001 and .001, respectively. Significant reductions in the mean pain intensity (90% of patients with lower VAS scores after intervention) and symptoms were reported. Four patients were classified as clinically unsuccessful, and were recommended further procedures for residual pain.ConclusionsCT fluoroscopy–guided transhepatic sclerotherapy is an effective, safe, and minimally invasive method to manage giant hepatic hemangiomas in an outpatient setting.     

Comparison of Bolus Versus Dual-Syringe Administration Systems on Glass Yttrium-90 Microsphere Deposition in an In Vitro Microvascular Hepatic Tumor Model

PurposeTo utilize an in vitro microvascular hepatic tumor model to compare the deposition characteristics of glass yttrium-90 microspheres using the dual-syringe (DS) and traditional bolus administration methods.Materials and MethodsThe microvascular tumor model represented a 3.5-cm tumor in a 1,400-cm³ liver with a total hepatic flow of 160 mL/min and was dynamically perfused. A microcatheter was placed in a 2-mm artery feeding the tumor model and 2 additional nontarget arteries. Glass microspheres with a diameter of 20–30 μm were administered using 2 methods: (a) DS delivery at a concentration of 50 mg/mL in either a single, continuous 2-mL infusion or two 1-mL infusions and (b) bolus delivery (BD) of 100 mg of microspheres in a single 3-mL infusion.ResultsOverall, the degree of on-target deposition of the microspheres was 85% ± 11%, with no significant differences between the administration methods. Although the distal penetration into the tumor arterioles was approximately 15 mm (from the second microvascular bifurcation of the tumor model) for all the cases, the distal peak particle counts were significantly higher for the DS delivery case (approximately 5 × 10⁵ microspheres achieving distal deposition vs 2 × 10⁵ for the BD case). This resulted in significantly higher deposition uniformity within the tumor model (90% for the DS delivery case vs 80% for the BD case, α = 0.05).ConclusionsThe use of this new in vitro microvascular hepatic tumor model demonstrated that the administration method can affect the deposition of yttrium-90 microspheres within a tumor, with greater distal deposition and more uniform tumor coverage when the microspheres are delivered at consistent concentrations using a DS delivery device. The BD administration method was associated with less favorable deposition characteristics of the microspheres.     

Cost Effectiveness of External Beam Radiation Therapy versus Percutaneous Image-Guided Cryoablation for Palliation of Uncomplicated Bone Metastases

PurposeTo evaluate the cost effectiveness of incorporating cryoablation in the treatment regimens for uncomplicated bone metastases using radiation therapy (RT) in single-fraction RT (SFRT) or multiple-fraction RT (MFRT) regimens.Materials and MethodsA Markov model was constructed using 1-month cycles over a lifetime horizon to compare the cost effectiveness of multiple strategies, including RT followed by RT (RT-RT) for recurrent pain, RT followed by cryoablation (RT-ablation), and cryoablation followed by RT (ablation-RT). RT-RT consisted of 8 Gy in 1 fraction/8 Gy in 1 fraction (SFRT-SFRT) and 30 Gy in 10 fractions/20 Gy in 5 fractions (MFRT-MFRT). Probabilities and utilities were extracted from a search of the medical literature. Costs were calculated from a payer perspective using 2017 Medicare reimbursement in an outpatient setting. Incremental cost effectiveness ratios (ICERs) were calculated using strategies evaluated for willingness-to-pay threshold of $100,000 per quality-adjusted life-year (QALY). To account for model uncertainty, one-way and probabilistic sensitivity analyses were performed.ResultsIn the base case analysis, SFRT-ablation was cost effective relative to SFRT-SFRT at $96,387/QALY. MFRT-ablation was cost effective relative to MFRT-MFRT at $85,576/QALY. Ablation-SFRT and ablation-MFRT were not cost effective with ICERs >$100,000/QALY. In one-way sensitivity analyses, results were highly sensitive to variation in multiple model parameters, including median survival (base: 9 months), with SFRT-SFRT favored at median survival ≤8.7 months. Probabilistic sensitivity analysis examining SFRT-based regimens showed that SFRT-ablation was preferred in 36.9% of simulations at WTP of $100,000/QALY.ConclusionsCryoablation is a potentially cost-effective alternative to reirradiation with RT for recurrent of pain following RT; however, no strategy incorporating initial cryoablation was cost effective.     

Hemodialysis Catheters in Infants: A Retrospective Single-Center Cohort Study

PurposeEvaluate technical aspects and outcomes of insertion/maintenance of hemodialysis (HD) central venous catheter (CVC) during infancy.Materials and MethodsSingle-center retrospective study of 29 infants who underwent 49 HD-CVC insertions between 2002 and 2016. Demographics, procedural, and post-procedural details, interventional radiology (IR) maintenance procedures, technical modifications, complications, and outcomes were evaluated. Technical adjustments during HD-CVC placement to adapt catheter length to patient size were labeled “modifications.” CVCs requiring return visit to IR were called IR-maintenance procedures. Mean age and weight at HD-CVC insertion were 117 days and 4.9 kg.ResultsOf the 29 patients, 13 (45%) required renal-replacement-therapy (RRT) as neonates, 10 (34%) commenced RRT with peritoneal dialysis (PD), and 19 (66%) with HD. Fifteen nontunneled and 34 tunneled HD-CVCs were inserted while patients were ≤1 year. Technical modifications were required placing 25/49 (51%) HD-CVCs: 5/15 (33%) nontunneled and 20/34 (59%) tunneled catheters (P = .08). Patients underwent ≤6 dialysis-cycles/patient during infancy (mean 2.3), and a mean of 4.1 and 49 HD-sessions/catheter for nontunneled and tunneled HD-CVCs, respectively. Mean primary and secondary device service, and total access site intervals for tunneled HD-CVCs were 75, 115, and 201 days, respectively. A total of 26 of 49 (53%) patients required IR-maintenance procedures. Nontunneled lines had greater catheter-related bloodstream infections per 1,000 catheter-days than tunneled HD-CVCs (9.25 vs. 0.85/1,000 catheter days; P = .02). Nineteen patients (65%) survived over 1 year. At final evaluation (December 2017): 8/19 survived transplantation, 5/19 remained on RRT, 2/19 completely recovered, 1/19 lost to follow-up, and 3 died at 1.3, 2, and 10 years.ConclusionsPlacement/maintenance of HD-CVCs in infants pose specific challenges, requiring insertion modifications, and IR-maintenance procedures to maintain function.