Fully automatic online geometric calibration for non-circular cone-beam CT orbits using fiducials with unknown placement.

BACKGROUND: Cone-beam CT (CBCT) with non-circular scanning orbits can improve image quality for 3D intraoperative image guidance. However, geometric calibration of such scans can be challenging. Existing methods typically require a prior image, specialized phantoms, presumed repeatable orbits, or long computation time. PURPOSE: We propose a novel fully automatic online geometric calibration algorithm that does not require prior knowledge of fiducial configuration. The algorithm is fast, accurate, and can accommodate arbitrary scanning orbits and fiducial configurations. METHODS: The algorithm uses an automatic initialization process to eliminate human intervention in fiducial localization and an iterative refinement process to ensure robustness and accuracy. We provide a detailed explanation and implementation of the proposed algorithm. Physical experiments on a lab test bench and a clinical robotic C-arm scanner were conducted to evaluate spatial resolution performance and robustness under realistic constraints. RESULTS: Qualitative and quantitative results from the physical experiments demonstrate high accuracy, efficiency, and robustness of the proposed method. The spatial resolution performance matched that of our existing benchmark method, which used a 3D-2D registration-based geometric calibration algorithm. CONCLUSIONS: We have demonstrated an automatic online geometric calibration method that delivers high spatial resolution and robustness performance. This methodology enables arbitrary scan trajectories and should facilitate translation of such acquisition methods in a clinical setting.

Relationship of Hepatocellular Carcinoma Stage and Hepatic Function to Health-Related Quality of Life: A Single Center Analysis.

Health-related quality of life (HRQoL) is known to be an important prognostic indicator and clinical endpoint for patients with hepatocellular carcinoma (HCC). However, the correlation of the Barcelona Clinic Liver Cancer (BCLC) stage with HRQoL in HCC has not been previously studied. We examined the relationship between BCLC stage, Child-Pugh (CP) score, and Eastern Cooperative Oncology Group (ECOG) performance status on HRQoL for patients who presented at a multidisciplinary liver cancer clinic. HRQoL was assessed using the Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep) questionnaire. Fifty-one patients met our inclusion criteria. The FACT-Hep total and subscales showed no significant association with BCLC stages (p = 0.224). Patients with CP B had significantly more impairment in FACT-Hep than patients with CP A. These data indicate that in patients with HCC, impaired liver function is associated with reduced quality of life, whereas the BCLC stage poorly correlates with quality of life metrics. Impairment of quality of life is common in HCC patients and further studies are warranted to determine the impact of early supportive interventions on HRQoL and survival outcomes.

Local Therapies for Metastatic Sarcoma: Why, When, and How?

Management of patients with advanced sarcoma has been evolving in recent decades, from a one-fit-all perspective to a more refined, personalized, and multidisciplinary approach. In parallel, the evolution of local therapies (radiotherapy, surgical and interventional radiology techniques) has contributed to the improvement of survival of patients with advanced sarcoma. In this article, we review the evidence regarding local treatments in advanced sarcoma, as well as its integration with systemic therapies, to provide the reader a wider and deeper perspective on the management of patients with metastatic sarcoma.

Clinical Outcomes of Percutaneous Biliary Endoscopy: A 7-Year Single-Institution Experience.

PURPOSE: To evaluate safety and effectiveness of percutaneous biliary endoscopy (PBE) performed on patients ineligible for surgery or endoscopic retrograde cholangiopancreatography. MATERIALS AND METHODS: Retrospective review was conducted for all patients who underwent PBE at a single academic institution between June 2013 and February 2020; 39 patients underwent 58 choledochoscopy sessions, and 21 patients underwent 48 cholecystoscopy sessions. Choledochoscopy indications included stone removal (23 of 39 patients) or biliary stenosis evaluation (19 of 39 patients). Cholecystoscopy indications included calculous cholecystitis (18 of 21 patients) and symptomatic cholelithiasis (3 of 21 patients). Technical success, procedural and fluoroscopy times, and tube-free survival were assessed. RESULTS: For all PBEs performed for stone clearance, using disposable endoscopes led to shorter mean ± SD procedural (128.7 minutes ± 56.2 vs 240.2 minutes ± 184.6; P < .01) and fluoroscopy times (10.7 minutes ± 7.9 vs 16.5 minutes ± 12.0; P = .01) than using reusable endoscopes. Increasing institutional experience was associated with reduced procedural time (ß = -56.73; P < .001). Choledochoscopy technical success was 94.8% with 1 adverse event of bile duct perforation with bile leak requiring drainage. For patients with choledocholithiasis, biliary drains were removed in 14 (60.9%) patients, with a mean tube-free survival of 22.1 months ± 23.8. For cholecystoscopy, technical success was 93.8% with no adverse events. Cholecystostomy tubes were removed in 15 (71.4%) patients, with a mean tube-free survival of 7.5 months ± 8.8. CONCLUSIONS: This study supports PBE as a safe and feasible option for nonsurgical patients or those with altered anatomy precluding endoscopic retrograde cholangiopancreatography. Moreover, PBE may result in tube-free survival.

MELD or MELD-Na as a Predictive Model for Mortality Following Transjugular Intrahepatic Portosystemic Shunt Placement.

Background and Aim: The model for end-stage liver disease (MELD) was originally developed to predict survival after transjugular intrahepatic portosystemic shunt (TIPS). The MELD-sodium (MELD-Na) score has replaced MELD for organ allocation for liver transplantation. However, there are limited studies to compare the MELD with MELD-Na to predict mortality after TIPS. Methods: We performed a retrospective chart review of patients who underwent TIPS placement between 2006 and 2016 at our institution. The primary outcome was mortality, and the secondary outcomes sought to assess which variables could provide prognostic information for mortality after TIPS placement. We performed receiver operating characteristic (ROC) curve analysis to assess the performance of MELD and MELD-Na. Results: There were 186 eligible patients in the analysis. The mean pre-TIPS MELD and MELD-Na were 13 and 15, respectively. Overall, mortality after TIPS was 15% at 30 days and 16.7% at 90 days. In a comparison of the areas under the ROCs for MELD and MELD-Na, MELD was superior to MELD-Na for 30-day (0.762 vs. 0.709) and 90-day (0.780 vs. 0.730) mortality after TIPS. The optimal cutoff score for 30-day mortality was 15 (0.676-0.848) for MELD and 17 (0.610-0.808) for MELD-Na, whereas the optimal cutoff score for 90-day mortality was 16 (95% CI: 0.705-0.855) for MELD and 17 (95% CI: 0.643-0.817) for MELD-Na. There were 24 patients with high MELD-Na ≥17, but with low MELD <15, and 90-day mortality in this group was 8.3%. Conclusions: Although MELD-Na is a superior prognostic tool to MELD for predicting overall mortality in cirrhotic patients, MELD tended to outperform MELD-Na to predict mortality after TIPS.

Association Between Gut Hormones and Weight Change After Bariatric Arterial Embolization: Results from the BEAT Obesity Trial.

PURPOSE: To evaluate associations of ghrelin, glucagon-like peptide 1 (GLP-1), and peptide YY 3-36 (PYY3-36) with weight change after bariatric arterial embolization (BAE). MATERIALS AND METHODS: Subgroup analysis of data collected during the BEAT Obesity Trial involving 7 participants with BMI > 40 who were embolized with 300- to 500-µm Embosphere Microspheres. Three participants were characterized as "responders" (top tertile of weight loss at each visit) and 4 as "non-responders" (bottom tertile of weight loss at each visit). Mean ± standard deviation participant age was 44 ± 11 years, and 6 of 7 participants were women. Participants were evaluated at baseline, 2 weeks, and 1, 3, 6, and 12 months after BAE. After fasting, participants consumed a mixed meal test at each visit; blood samples were collected at 0, 15, 30, 60, 120, 180, and 240 min. Study outcome measures were changes in weight from baseline and plasma serum hormone levels. RESULTS: Percentage change in ghrelin decreased significantly in non-responders at 60 and 120 min at 1 and 12 months (estimated difference between 60 vs. 0 min at 1 month: 69% [95% CI - 126%, - 13%]; estimated difference between 120 vs. 0 min at 12 months: - 131% (95% CI - 239%, - 23%]). Responders had significantly lower ghrelin and greater weight loss than non-responders at 6 and 12 months. GLP-1 and PYY3-36 levels did not differ between groups. CONCLUSION: Participants with consistent weight loss throughout follow-up had lower ghrelin than non-responders, supporting decreased ghrelin as a mechanism underlying BAE-induced weight loss. LEVEL OF EVIDENCE I: High-quality randomized trial or prospective study; testing of previously developed diagnostic criteria on consecutive patients; sensible costs and alternatives; values obtained from many studies with multiway sensitivity analyses; systematic review of Level I RCTs and Level I studies.

Conventional vs. Drug-Eluting Beads Transarterial Chemoembolization for Unresectable Hepatocellular Carcinoma-A Propensity Score Weighted Comparison of Efficacy and Safety.

This study compared the efficacy and safety of conventional transarterial chemoembolization (cTACE) with drug-eluting beads (DEB)-TACE in patients with unresectable hepatocellular carcinoma (HCC). This retrospective analysis included 370 patients with HCC treated with cTACE (n = 248) or DEB-TACE (n = 122) (January 2000-July 2014). Overall survival (OS) was assessed using uni- and multivariate Cox proportional hazards models and Kaplan-Meier analysis. Additionally, baseline imaging was assessed, and clinical and laboratory toxicities were recorded. Propensity score weighting via a generalized boosted model was applied to account for group heterogeneity. There was no significant difference in OS between cTACE (20 months) and DEB-TACE patients (24.3 months, ratio 1.271, 95% confidence interval 0.876-1.69; p = 0.392). However, in patients with infiltrative disease, cTACE achieved longer OS (25.1 months) compared to DEB-TACE (9.2 months, ratio 0.366, 0.191-0.702; p = 0.003), whereas DEB-TACE proved more effective in nodular disease (39.4 months) than cTACE (18 months, ratio 0.458, 0.308-0681; p = 0.007). Adverse events occurred with similar frequency, except for abdominal pain, which was observed more frequently after DEB-TACE (101/116; 87.1%) than cTACE (119/157; 75.8%; p = 0.02). In conclusion, these findings suggest that tumor morphology and distribution should be used as parameters to inform decisions on the selection of embolic materials for TACE for a more personalized treatment planning in patients with unresectable HCC.

Bronchial Artery Chemoembolization With Radiopaque Doxorubicin Eluding Beads in Patients With Malignant Hemoptysis from Metastatic Lung Cancer.

Purpose:This pilot study was designed to assess the technical feasibility and safety of bronchial artery chemoembolization with radiopaque doxorubicin eluting beads (DEB-BACE) in patients with malignant hemoptysis from pulmonary metastasis. Materials & Methods: Four patients underwent DEB-BACE using 70-150 µm radiopaque DEB (LC Beads LUMI, Boston Scientific). Beads delivery and deposition were assessed under fluoroscopy and cone beam computed tomography (CT), respectively. Results: All 4 procedures were technically successful. Beads delivery and deposition were successfully visualized under fluoroscopy and cone beam CT guidance in all cases. Hemoptysis was resolved after embolization in all 4 patients. There were no adverse events or immediate or early complications after DEB-BACE. Two patients (50%) required repeat DEB-BACE within 1 week due to recurrent hemoptysis, and 1 patient had DEB-BACE 1.5 years later due to recurrent hemoptysis from the contralateral lung. All targeted lesions decreased in size in follow-up studies (mean 16 months, range 1-33 months). One patient died of progressive cancer disease invading the heart 1 month after DEB-BACE. Conclusions: DEB-BACE using radiopaque LC Beads LUMI loaded with doxorubicin is technically feasible and safe for controlling hemoptysis and cancer progression in patients with metastatic lung tumors. Visualization of beads delivery under fluoroscopy and deposition of beads under cone beam CT facilitate delivery of beads and embolization of bronchial arteries.

Analysis of Tumor Burden as a Biomarker for Patient Survival with Neuroendocrine Tumor Liver Metastases Undergoing Intra-Arterial Therapies: A Single-Center Retrospective Analysis.

PURPOSE: To assess the value of quantitative analysis of tumor burden on baseline MRI for prediction of survival in patients with neuroendocrine tumor liver metastases (NELM) undergoing intra-arterial therapies. MATERIALS AND METHODS: This retrospective single-center analysis included 122 patients with NELM who received conventional (n = 74) or drug-eluting beads, (n = 20) chemoembolization and radioembolization (n = 28) from 2000 to 2014. Overall tumor diameter (1D) and area (2D) of up to 3 largest liver lesions were measured on baseline arterially contrast enhanced MR images. Three-dimensional quantitative analysis was performed using the qEASL tool (IntelliSpace Portal Version 8, Philips) to calculate enhancing tumor burden (the ratio between enhancing tumor volume and total liver volume). Based on Q-statistics, patients were stratified into low tumor burden (TB) or high TB. RESULTS: The survival curves were significantly separated between low TB and high TB groups for 1D (p < 0.001), 2D (p < 0.001) and enhancing TB (p = 0.008) measurements, with, respectively, 2.7, 2.6 and 2.2 times longer median overall survival (MOS) in the low TB group (p < 0.001, p < 0.001 and p = 0.008). Multivariate analysis showed that 1D, 2D, and enhancing TB were independent prognostic factors for MOS, with respective hazard ratios of 0.4 (95%CI: 0.2-0.6, p < 0.001), 0.4 (95%CI: 0.3-0.7, p < 0.001) and 0.5 (95%CI: 0.3-0.8, p = 0.003). CONCLUSION: The overall tumor diameter, overall tumor area, and enhancing tumor burden are strong prognostic factors of overall survival in patients with neuroendocrine tumor liver metastases undergoing intra-arterial therapies.

Percutaneous Cholangioscopy for the Diagnosis and Management of Biliary Pathology in Pediatric Patients: A Single-Center Experience.

Transhepatic percutaneous cholangioscopy (PC) can be used for the diagnosis and treatment of biliary pathology. It allows for direct visualization of the biliary system to identify pathologic changes, perform biopsies, and treat biliary obstruction. The effectiveness and safety of PC in adults have been established. However, the data on the use of PC in pediatric patients are limited. In this case series, the outcomes in 4 pediatric patients (3 girls; mean age, 4 [range, 1-8] years) who underwent 6 PC procedures were examined. Three out of the 6 (50%) PC procedures were performed for diagnostic visualization of the biliary tree and/or small intestine, whereas the remaining 3 (50%) were performed for the treatment of biliary obstruction causing chronic cholestasis. The technical and procedural success rate was 100%, and no complications were encountered during or 30 days after the procedure. This study supports the feasibility and safety of PC in pediatric patients for the management of biliary pathology.

Three-Dimensional Quantitative Tumor Response and Survival Analysis of Hepatocellular Carcinoma Patients Who Failed Initial Transarterial Chemoembolization: Repeat or Switch Treatment?

OBJECTIVES: The purpose of this study was to assess treatment responses and evaluate survival outcomes between responders and non-responders after each transarterial chemoembolization (TACE) session using the 3D quantitative criteria of the European Association for the Study of the Liver (qEASL) in hepatocellular carcinoma (HCC) patients. METHODS: A total of 94 consecutive patients who underwent MR imaging before and after TACE were retrospectively included. Volumetric tumor enhancement (qEASL) was expressed in cubic centimeters (cm3). The Kaplan-Meier method with the log-rank test was used to calculate the overall survival (OS) for the non-/responders. RESULTS: In total, 28 (29.8%) patients showed a response after the first TACE. These responders demonstrated a clear trend toward longer OS compared with the non-responders (36.7 vs. 21.5 months, p = 0.071). Of the 43 initial non-responders who underwent a second TACE within 3 months and had complete follow-up imaging, 15/43 (34.9%) achieved a response, and their median OS was significantly longer than that of the 28 non-responders to the second TACE (47.8 vs. 13.6 months, p = 0.01). Furthermore, there was no significant difference in OS between the 28 patients who achieved a response after the first TACE and the 15 initial non-responders who achieved a response after the second TACE (36.7 vs. 47.8 months, p = 0.701). The difference in OS between the responders and non-responders after the third TACE was not significant (11.4 months vs. 13.5 months, p = 0.986). CONCLUSION: Our study quantitatively demonstrated that a second TACE can be beneficial in terms of tumor response and survival for HCC patients who do not initially respond to TACE.

Response assessment methods for patients with hepatic metastasis from rare tumor primaries undergoing transarterial chemoembolization.

PURPOSE: This study assessed the response to conventional transarterial chemoembolization (cTACE) in patients with liver metastases from rare tumor primaries using one-dimensional (1D) and three-dimensional (3D) quantitative response assessment methods, and investigate the relationship of lipiodol deposition in predicting response. MATERIALS AND METHODS: This retrospective bicentric study included 16 patients with hepatic metastases from rare tumors treated with cTACE between 2002 and 2017. Multi-phasic MR imaging obtained before and after cTACE was used for assessment of response. Response evaluation criteria in solid tumors (RECIST) and modified-RECIST (mRECIST) were utilized for 1D response assessment, and volumetric RECIST (vRECIST) and enhancement-based quantitative European Association for Study of the Liver EASL (qEASL) were used for 3D response assessment. The same day post-cTACE CT scan was analyzed to quantify intratumoral lipiodol deposition (%). RESULTS: The mean and standard deviation (SD) of diameter of treated lesions per targeted area was 7.5 ± 5.4 cm, and the mean and SD of number of metastases in each targeted area was 4.2 ± 4.6. cTACE was technically successful in all patients, without major complications. While RECIST and vRECIST methods did not allocate patients with partial response, mRECIST and qEASL identified patients with partial response. Intratumoral lipiodol deposition significantly predicted treatment response according qEASL (R2 = 0.470, p < 0.01), while no association was shown between lipiodol deposition within treated tumor area and RECIST or mRECIST (p > 0.212). CONCLUSION: 3D quantitative volumetric response analysis can be used for stratification of response to cTACE in patients with hepatic metastases originating from rare primary tumors. Lipiodol deposition could potentially be used as an early surrogate to predict response to cTACE.

Radiofrequency Ablation versus Transarterial Chemoembolization in Patients with Hepatocellular Carcinoma Awaiting Liver Transplant: An Analysis of the Scientific Registry of Transplant Recipients.

PURPOSE: To evaluate differences in waitlist mortality and dropout in liver transplant candidates with hepatocellular carcinoma (HCC) who undergo radiofrequency (RF) ablation versus transarterial chemoembolization (TACE). MATERIAL AND METHODS: From 2004 to 2013, 11,824 patients with HCC in the Scientific Registry of Transplant Recipients who underwent RF ablation or TACE were included and followed until December 31, 2019, or 5 years, whichever came first, and were stratified by the Milan criteria. Competing risk and Cox regression analyses to compare waitlist mortality and dropout were performed using adjusted hazard ratios (asHRs, with RF ablation group as reference). Regression models were adjusted for age, race, sex, calculated Model for End-Stage Liver Disease score, tumor size, and number. RESULTS: There was no difference in waitlist mortality and dropout for patients outside the Milan criteria (n = 1,226) who underwent TACE (19.2%) or RF ablation (19.0%) (asHR, 0.91; 95% CI, 0.79-1.03). There was also no difference for patients inside the Milan criteria (n = 10,598) in waitlist mortality/dropout (TACE 13.4% vs RF ablation 12.9%) (asHR, 1.29; 95% CI, 0.79-2.09). A subgroup analysis within the Milan criteria demonstrated no difference between TACE and RF ablation treatments in patients with a single tumor of ≤3 cm (asHR, 0.92; 95% CI, 0.77-1.10), with a single tumor of >3 cm (asHR, 1.03; 95% CI, 0.79-1.34), or with >1 tumor (asHR, 0.89; 95% CI, 0.72-1.09). CONCLUSIONS: Using the national registry data, no difference was found in waitlist mortality and dropout for transplant candidates with HCC who received TACE versus RF ablation.

Non-circular CBCT orbit design and realization on a clinical robotic C-arm for metal artifact reduction.

Metal artifacts have been a difficult challenge for cone-beam CT (CBCT), especially for intraoperative imaging. Metal surgical tools and implants are often present in the field of view and can attenuate X-rays so heavily that they essentially create a missing-data problem. Recently, an increasing number of intra-operative imaging systems such as robotic C-arms are capable of non-circular orbits for data acquisition. Such trajectories can potentially improve sampling and the degree of data completeness to solve the metal-induced missing-data problem, thereby reducing or eliminating the associated image artifacts. In this work, we extend our prior theoretical and experimental work and implement non-circular orbits for metal artifact reduction on a clinical robotic C-arm (Siemens Artis zeego). To maximize the potential for clinical translation, we restrict our implementation to standard built-in motion and data collection functions, also available on other zeego systems, and work within the physical constraints and limitations on positioning and motion. Customized software tools for data extraction, processing, calibration, and reconstruction are used. We demonstrate example non-circular orbits and the resulting image quality using a phantom containing pedicle screws for spine fixation. As compared with a standard circular CBCT orbit, these non-circular orbits exhibit significantly reduced metal artifacts. These results suggest a high potential for image quality improvements for intraoperative CBCT imaging when metal tools or implants are present in the field-of-view.

Optimization of the BCLC Staging System for Locoregional Therapy for Hepatocellular Carcinoma by Using Quantitative Tumor Burden Imaging Biomarkers at MRI.

Background Patients with intermediate- and advanced-stage hepatocellular carcinoma (HCC) represent a highly heterogeneous patient collective with substantial differences in overall survival. Purpose To evaluate enhancing tumor volume (ETV) and enhancing tumor burden (ETB) as new criteria within the Barcelona Clinic Liver Cancer (BCLC) staging system for optimized allocation of patients with intermediate- and advanced-stage HCC to undergo transarterial chemoembolization (TACE). Materials and Methods In this retrospective study, 682 patients with HCC who underwent conventional TACE or TACE with drug-eluting beads from January 2000 to December 2014 were evaluated. Quantitative three-dimensional analysis of contrast-enhanced MRI was performed to determine thresholds of ETV and ETB (ratio of ETV to normal liver volume). Patients with ETV below 65 cm3 or ETB below 4% were reassigned to BCLC Bn, whereas patients with ETV or ETB above the determined cutoffs were restratified or remained in BCLC Cn by means of stepwise verification of the median overall survival (mOS). Results This study included 494 patients (median age, 62 years [IQR, 56-71 years]; 401 men). Originally, 123 patients were classified as BCLC B with mOS of 24.3 months (95% CI: 21.4, 32.9) and 371 patients as BCLC C with mOS of 11.9 months (95% CI: 10.5, 14.8). The mOS of all included patients (including the BCLC B and C groups) was 15 months (95% CI: 12.3, 17.2). A total of 152 patients with BCLC C tumors were restratified into a new BCLC Bn class, in which the mOS was then 25.1 months (95% CI: 21.8, 29.7; P < .001). The mOS of the remaining patients (ie, BCLC Cn group) (n = 222; ETV ≥65 cm3 or ETB ≥4%) was 8.4 months (95% CI: 6.1, 11.2). Conclusion Substratification of patients with intermediate- and advanced-stage hepatocellular carcinoma according to three-dimensional quantitative tumor burden identified patients with a survival benefit from transarterial chemoembolization before therapy. © RSNA, 2022 Online supplemental material is available for this article.

Incidence and Contemporary Management of Delayed Bleeding Following Pancreaticoduodenectomy.

BACKGROUND: Delayed bleeding after pancreaticoduodenectomy (PD) is a life-threatening complication. However, the optimal management remains unclear. We summarize our experience of the management of delayed bleeding after PD and define the outcomes associated with different types of management. METHODS: All patients who underwent a PD between January 1987 and June 2020 at Johns Hopkins University were retrospectively reviewed. Delayed bleeding was defined as bleeding on or after postoperative day 5 following PD. Incidence, outcomes, and trends were reported. RESULTS: Among the 6201 patients that underwent PD, delayed bleeding occurred in 130 (2.1%) at a median of 12 days (IQR: 9, 24) postoperation. The pattern of bleeding was classified as intraluminal (51.5%), extraluminal (40.8%), and mixed (7.7%). A clinically relevant postoperative pancreatic fistula and an intraabdominal abscess preceded the delayed bleeding in 43.1% and 31.5% of cases, respectively. Arterial pseudoaneurysm or bleeding from peripancreatic vessels was the most common reason (54.6%) with the gastroduodenal artery being the most common source (18.5%). Endoscopy, angiography, and reoperation were performed as a first-line approach in 35.4%, 52.3%, and 6.2% of patients, respectively. The overall mortality was 16.2% and decreased over the study period (p < 0.01). CONCLUSIONS: Delayed bleeding following PD remains a life-threatening complication. The most common location of delayed bleeding is from the gastroduodenal artery. Angiography with embolization should be the initial approach for urgent bleeding with surgical re-exploration reserved for unstable patients or failed control of bleeding after interventional angiography or endoscopy.

Impact of the COVID-19 Pandemic on Liver Cancer Staging at a Multidisciplinary Liver Cancer Clinic.

To compare liver cancer resectability rates before and during the COVID-19 pandemic. Background: Liver cancers usually present with nonspecific symptoms or are diagnosed through screening programs for at-risk patients, and early detection can improve patient outcomes. In 2020, the COVID-19 pandemic upended medical care across all specialties, but whether the pandemic was associated with delays in liver cancer diagnosis is not known. Methods: We performed a retrospective review of all patients evaluated at the Johns Hopkins Multidisciplinary Liver Cancer Clinic from January 2019 to June 2021 with a new diagnosis of suspected or confirmed hepatocellular carcinoma (HCC) or biliary tract cancer (BTC). Results: There were 456 liver cancer patients (258 HCC and 198 BTC). From January 2019 to March 2020 (pre-pandemic), the surgical resectability rate was 20%. The subsequent 6 months (early pandemic), the resectability rate decreased to 11%. Afterward from October 2020 to June 2021 (late pandemic), the resectability rate increased to 27%. The resectability rate early pandemic was significantly lower than that for pre-pandemic and later pandemic combined (11% lower; 95% confidence interval [CI], 2%-20%). There was no significant difference in resectability rates pre-pandemic and later pandemic (7% difference; 95% CI, -3% to 16%). In subgroup analyses, the early pandemic was associated with a larger impact in BTC resectability rates than HCC resectability rates. Time from BTC symptom onset until Multidisciplinary Liver Clinic evaluation increased by over 6 weeks early pandemic versus pre-pandemic (Hazard Ratio, 0.63; 95% CI, 0.44-0.91). Conclusions: During the early COVID-19 pandemic, we observed a drop in the percentage of patients presenting with curable liver cancers. This may reflect delays in liver cancer diagnosis and contribute to excess mortality related to the COVID-19 pandemic.

Single-Use versus Reusable Endoscopes for Percutaneous Biliary Endoscopy with Lithotripsy: Technical Metrics, Clinical Outcomes, and Cost Comparison.

PURPOSE: To compare procedure and fluoroscopy time, technical and clinical success, and costs between single-use and reusable endoscopes in patients undergoing percutaneous biliary endoscopy (PBE) with lithotripsy. MATERIAL AND METHODS: Thirty-four patients (67 procedures) were retrospectively included in the study. The patients were treated with PBE for gallstone removal from October 24, 2014, to February 12, 2020, using reusable (28 procedures) or single-use (39 procedures) endoscopes. The procedure time, fluoroscopy time, technical success rate (accessing the biliary system and locating the gallstone), clinical success rate (at least partial gallstone removal), complication rate, and cost of use were compared between the procedures. RESULTS: The mean (± standard deviation) procedure time was not significantly different between single-use (136 minutes ± 45) and reusable endoscopes (136 minutes ± 51) (P = .47). The mean fluoroscopy time was significantly shorter for single-use endoscopes (11 minutes ± 8.4) than for reusable endoscopes (18 minutes ± 12) (P = .01). When comparing single-use versus reusable endoscopes, the technical success (95% [n = 37] vs 93% [n = 26]) and the clinical success (90% [n = 35] vs 75% [n = 21]) rates were not significantly different (both, P > .05). Only 1 complication was noted in the reusable endoscope group (P = .42). The cost per case was lower for single-use ($1,500) than for reusable ($3,987) endoscope procedures, primarily due to differences in capital costs and repair costs. CONCLUSIONS: Single-use endoscopes offer the potential for lower patient radiation exposure and lower cost per case, which may reduce the financial barriers to offering PBE in interventional radiology practices. The clinical and technical success rates did not differ by endoscope type.

Practical workflow for arbitrary non-circular orbits for CT with clinical robotic C-arms.

Non-circular orbits in cone-beam CT (CBCT) imaging are increasingly being studied for potential benefits in field-of-view, dose reduction, improved image quality, minimal interference in guided procedures, metal artifact reduction, and more. While modern imaging systems such as robotic C-arms are enabling more freedom in potential orbit designs, practical implementation on such clinical systems remains challenging due to obstacles in critical stages of the workflow, including orbit realization, geometric calibration, and reconstruction. In this work, we build upon previous successes in clinical implementation and address key challenges in the geometric calibration stage with a novel calibration method. The resulting workflow eliminates the need for prior patient scans or dedicated calibration phantoms, and can be conducted in clinically relevant processing times.