Percutaneous CT-Guided Abdominal and Pelvic Biopsies: Comparison of an Electromagnetic Navigation System and CT Fluoroscopy

PurposeTo compare electromagnetic navigation (EMN) with computed tomography (CT) fluoroscopy for guiding percutaneous biopsies in the abdomen and pelvis.Materials and MethodsA retrospective matched-cohort design was used to compare biopsies in the abdomen and pelvis performed with EMN (consecutive cases, n = 50; CT-Navigation; Imactis, Saint-Martin-d’Hères, France) with those performed with CT fluoroscopy (n = 100). Cases were matched 1:2 (EMN:CT fluoroscopy) for target organ and lesion size (±10 mm).ResultsThe population was well-matched (age, 65 vs 65 years; target size, 2.0 vs 2.1 cm; skin-to-target distance, 11.4 vs 10.7 cm; P > .05, EMN vs CT fluoroscopy, respectively). Technical success (98% vs 100%), diagnostic yield (98% vs 95%), adverse events (2% vs 5%), and procedure time (33 minutes vs 31 minutes) were not statistically different (P > .05). Operator radiation dose was less with EMN than with CT fluoroscopy (0.04 vs 1.2 μGy; P < .001), but patient dose was greater (30.1 vs 9.6 mSv; P < .001) owing to more helical scans during EMN guidance (3.9 vs 2.1; P < .001). CT fluoroscopy was performed with a mean of 29.7 tap scans per case. In 3 (3%) cases, CT fluoroscopy was performed with gantry tilt, and the mean angle out of plane for EMN cases was 13.4°.ConclusionsPercutaneous biopsies guided by EMN and CT fluoroscopy were closely matched for technical success, diagnostic yield, procedure time, and adverse events in a matched cohort of patients. EMN cases were more likely to be performed outside of the gantry plane. Radiation dose to the operator was higher with CT fluoroscopy, and patient radiation dose was higher with EMN. Further study with a wider array of procedures and anatomic locations is warranted.     

Positron Emission Tomography and Computed Tomography Contributions to Patient Dose and Personnel Exposure to Radiation during PET/CT-Guided Tumor Ablations

This study sought to quantify the positron emission tomography (PET) and computed tomography (CT) components of patient radiation doses and personnel exposure to radiations during PET/CT-guided tumor ablations and assess the utility of a rolling lead shield for operator protection. Two operators performed 21 PET/CT-guided ablations behind a customized, 25-mm-thick lead shield with midchest-to-midthigh coverage. The mean patient radiation dose per procedure was 3.90 mSv ± 1.13 (11.3%) from PET and 30.51 mSv ± 19.05 (88.7%) from CT. The mean primary and secondary operator exposure outside neck-level thyroid shields was 0.05 and 0.02 mSv per procedure, respectively. The radiation exposure levels behind the rolling lead shield, inside the primary operator’s thyroid shield, and on the other personnel were below the measurable threshold cumulatively over 21 procedures. The mean PET exposure level at continuous close proximity to patients was 0.02 mSv per procedure. The PET radiation doses to the patients and personnel were small. Thus, the rolling lead shield provided limited benefit.     

Improved Utilization Following Conversion of a Fluoroscopy Suite to Hybrid CT/Angiography System

PurposeTo assess changes in operational utilization following conversion of a single IR suite to a hybrid CT/angiography (Angio-CT) system at an academic tertiary care center.Materials and MethodsThe total number of interventional procedures and diagnostic CT examinations performed in 29 rooms (20 diagnostic radiology, 7 IR, 2 shared between divisions) was calculated in the 24 months before conversion of an IR suite to Angio-CT and 12 months after conversion. The total number of IR procedures (global IR/month) and diagnostic CT scans per month (global CT/month) in both before and after conversion periods was calculated and defined as baseline institutional growth. This was compared against the change in the number of IR procedures performed in the before and after periods in the converted room (Angio-CT/month) as well as the number of diagnostic CT scans performed in the shared rooms (shared CT/month).ResultsThe percent change in global CT and global IR from the before to the after periods was 39.2% and 3.1%, respectively. Shared CT per month and Angio-CT per month increased by 46.7% and 12.0% across the same time periods, respectively. The ratio of the percent increase in Angio-CT per month to percent increase in global IR per month was 3.87. The ratio of the percent increase in shared CT per month to percent increase in global CT per month was 1.19.ConclusionsOperational utilization improved in both diagnostic radiology and IR sections following conversion of a conventional fluoroscopic IR suite to an Angio-CT room.     

CT Fluoroscopy for Image-Guided Procedures: Physician Radiation Dose During Full-Rotation and Partial-Angle CT Scanning

PurposeTo determine physician radiation exposure when using partial-angle computed tomography (CT) fluoroscopy (PACT) vs conventional full-rotation CT and whether there is an optimal tube/detector position at which physician dose is minimized.Materials and MethodsPhysician radiation dose (entrance air kerma) was measured for full-rotation CT (360°) and PACT (240°) at all tube/detector positions using a human-mimicking phantom placed in a 64-channel multidetector CT. Parameters included 120 kV, 20- and 40-mm collimation, and 100 mA. The mean, standard deviation, and increase/decrease in physician dose compared with a full-rotation scan were reported.ResultsPhysician radiation exposure during CT fluoroscopy with PACT was highly dependent on the position of the tube/detector during scanning. The lowest PACT physician dose was when the physician was on the detector side (center view angle 116°; ?35% decreased dose vs full-angle CT). The highest PACT physician dose was with the physician on the tube side (center view angle 298°; +34% increased dose vs full-angle CT), all doses P <.05 vs full-rotation CT.ConclusionsPartial-angle CT has the potential to both significantly increase or decrease physician radiation dose during CT fluoroscopy-guided procedures. The detector/tube position has a profound effect on physician dose. The lowest dose during PACT was achieved when the physician was located on the detector side (ie, distant from the tube). This data could be used to optimize CT fluoroscopy parameters to reduce physician radiation exposure for PACT-capable scanners.     

Tumor and Ablation Margin Visibility during Cryoablation of Musculoskeletal Tumors: Comparing Intraprocedural PET/CT Images with CT-Only Images

PurposeTo compare tumor and ice-ball margin visibility on intraprocedural positron emission tomography (PET)/computed tomography (CT) and CT-only images and report technical success, local tumor progression, and adverse event rates for PET/CT-guided cryoablation procedures for musculoskeletal tumors.Materials and MethodsThis Health Insurance Portability and Accountability Act (HIPAA)–compliant and institutional review board–approved retrospective study evaluated 20 PET/CT-guided cryoablation procedures performed with palliative and/or curative intent to treat 15 musculoskeletal tumors in 15 patients from 2012 to 2021. Cryoablation was performed using general anesthesia and PET/CT guidance. Procedural images were reviewed to determine the following: (a) whether the tumor borders could be fully assessed on PET/CT or CT-only images; and (b) whether tumor ice-ball margins could be fully assessed on PET/CT or CT-only images. The ability to visualize tumor borders and ice-ball margins on PET/CT images was compared with that on CT-only images.ResultsTumor borders were fully assessable for 100% (20 of 20; 95% CI, 0.83–1) of procedures on PET/CT versus 20% (4 of 20; 95 CI, 0.057–0.44) of procedures on CT only (P < .001). The tumor ice-ball margin was fully assessable in 80% (16 of 20; 95% CI, 0.56–0.94) of procedures using PET/CT versus 5% (1 of 20; 95% CI, 0.0013–0.25) of procedures using CT only (P < .001). Primary technical success was achieved in 75% (15 of 20; 95% CI, 0.51–0.91) of procedures. There was local tumor progression in 23% (3/13; 95% CI, 0.050–0.54) of the treated tumors with at least 6 months of follow-up. There were 3 adverse events (1 Grade 3, 1 Grade 2, and 1 Grade 1).ConclusionsPET/CT-guided cryoablation of musculoskeletal tumors can provide superior intraprocedural visualization of the tumor and ice-ball margins compared with that provided by CT alone. Further studies are warranted to confirm the long-term efficacy and safety of this approach.     

Transarterial Radioembolization with Yttrium-90 Glass Microspheres: Distribution of Residual Activity and Flow Dynamics during Administration

PurposeTo evaluate the microsphere flow dynamics and residual yttrium-90 (⁹⁰Y) activity during and after transarterial radioembolization with glass microspheres and to assess the distribution and predilection sites of residual activity in the administration devices.Materials and MethodsIn this laboratory investigation, after 18 consecutive clinical transarterial radioembolization and 4 ex vivo experimental procedures with ⁹⁰Y glass microspheres, the distribution of residual activity in the administration devices was assessed by activimeter and positron emission tomography (PET)/CT measurements. During ex vivo procedures, microsphere outflow from the administration device was assessed by dynamic scintigraphic measurements.ResultsMean residual activity was 3.4% ± 1.7 (range, 0.9%–8.8%). Calculations showed a negative correlation between relative residual activity and prescribed activity (r = −0.4258, P = .0486) and a positive correlation between absolute residual activity and prescribed activity (r = 0.5345, P = .0104). The main predilection site was the Luer-Lok microcatheter connector. Lower activities were detected in the dose vial. Flow measurements showed that more than 98% of the final injected activity was transferred to the patient with the first 20 mL of saline solution.ConclusionsResidual activity in the standard administration device for glass microsphere radioembolization is considered to be low compared with similar procedures, but is variable. The microsphere flow profile shows an initial peak, resulting in a rapid activity transfer at the beginning of the injection process. The findings may have implications for safe handling of the administration device and for dose calculation of ⁹⁰Y glass microspheres.     

Liver Tumor Ablation Procedure Duration and Estimated Patient Radiation Dose: Comparing Positron Emission Tomography/CT and CT Guidance

PurposeTo compare procedure duration and patient radiation dose in positron emission tomography/computed tomography (PET/CT) and CT-guided liver tumor ablation procedures.Materials and MethodsIn this retrospective, case-control study, 275 patients underwent 368 image-guided ablation procedures to treat 537 tumors. Radiologists used PET/CT guidance for 117 procedures and CT guidance for 251 procedures. PET/CT-guided procedures were performed by one radiologist (C: P.B.S.). All 3 radiologists (A: J.G.S., B: a radiologist who is not an author on this article, and C: P.B.S.) performed CT-guided procedures. Potential confounders included patient demographics, clinical and tumor characteristics, and procedural variables.ResultsThe mean duration and estimated patient radiation dose of PET/CT-guided procedures performed by radiologist C were 21.5 ± 4.9 minutes longer and 0.7 ± 2.8 mSv higher than CT-guided procedures performed by all radiologists in an unadjusted comparison. Adjusting for confounding, mean duration and estimated dose of PET/CT-guided procedures performed by radiologist C were 28.3 ± 3.8 minutes longer (P < .0001) and 6.2 ± 2.9 mSv higher (P = .03) than CT-guided procedures performed by the same radiologist. Comparing CT-guided procedures performed by all 3 radiologists, adjusted mean durations and estimated patient doses of procedures by the least experienced radiologist, radiologist A, and the second most experienced radiologist, radiologist B, were 24.2 ± 5.1 (P < .0001) and 18.1 ± 8.9 (P = .04) minutes longer and 13.1 ± 3.7 (P < .001) and 14.5 ± 6.4 (P = .02) mSv higher, respectively, than procedures performed by the most experienced radiologist, radiologist C.ConclusionsPET/CT-guided liver ablations had a slightly longer duration with slightly higher estimated patient radiation dose than similar CT-guided liver ablations. Procedure duration and patient dose do not appear to be major impediments to the emerging field of PET/CT-guided tumor ablation.     

Methylene Blue/Collagen Mixture for CT-Guided Presurgical Lung Nodule Marking: High Efficacy and Safety

PurposeTo assess outcomes of computed tomography (CT)-guided methylene blue/collagen marking of preoperative lung nodules before video-assisted thoracoscopic surgery (VATS) and robotic-assisted thoracic surgery (RATS).Materials and MethodsA retrospective cohort study assessing 25 methylene blue/collagen solution CT-guided lung nodule localization procedures on 26 nodules in 25 patients was performed. The procedures were performed by a fellowship-trained radiologist 1–2 hours before scheduled surgery under local anesthesia. Approximately 4–6 ml of methylene blue/collagen solution was injected in a perinodular location under CT guidance with a 19-gauge trocar needle and along the track to the visceral pleural surface. Post-procedural CT images confirmed appropriate lung nodule location marking.ResultsPerinodular CT-guided trocar needle placement was achieved in all marking procedures (n = 26/26). Increased consolidation near the target nodule was also demonstrated in all patients on the post-procedural localized CT scans. One patient with moderate emphysema developed a small to moderate-sized pneumothorax (∼20%–30%), and an 8-Fr thoracentesis catheter was placed under CT guidance before surgery. There was no bleeding or hemoptysis in any patient. Methylene blue/collagen solution was readily visible by the thoracic surgeon in association with all target nodules. One patient required conversion to open procedure due to the proximal portion of the right lower lobe pulmonary artery segmental branch. Of the 26 identified nodules, pathology specimens confirmed the adequacy of nodule resection in all cases.ConclusionsPreoperative CT-guided methylene blue/collagen solution injection offers a safe and highly effective technique for marking subpleural lung nodules undergoing VATS or RATS.     

Yttrium-90 Activity Quantification in PET/CT–Guided Biopsy Specimens from Colorectal Hepatic Metastases Immediately after Transarterial Radioembolization Using Micro–CT and Autoradiography

PurposeTo evaluate the yttrium-90 (⁹⁰Y) activity distribution in biopsy tissue samples of the treated liver to quantify the dose with higher spatial resolution than positron emission tomography (PET) for accurate investigation of correlations with microscopic biological effects and to evaluate the radiation safety of this procedure.Materials and MethodsEighty-six core biopsy specimens were obtained from 18 colorectal liver metastases (CLMs) immediately after ⁹⁰Y transarterial radioembolization (TARE) with either resin or glass microspheres using real-time ⁹⁰Y PET/CT guidance in 17 patients. A high-resolution micro–computed tomography (micro-CT) scanner was used to image the microspheres in part of the specimens and allow quantification of ⁹⁰Y activity directly or by calibrating autoradiography (ARG) images. The mean doses to the specimens were derived from the measured specimens’ activity concentrations and from the PET/CT scan at the location of the biopsy needle tip for all cases. Staff exposures were monitored.ResultsThe mean measured ⁹⁰Y activity concentration in the CLM specimens at time of infusion was 2.4 ± 4.0 MBq/mL. The biopsies revealed higher activity heterogeneity than PET. Radiation exposure to the interventional radiologists during post-TARE biopsy procedures was minimal.ConclusionsCounting the microspheres and measuring the activity in biopsy specimens obtained after TARE are safe and feasible and can be used to determine the administered activity and its distribution in the treated and biopsied liver tissue with high spatial resolution. Complementing ⁹⁰Y PET/CT imaging with this approach promises to yield more accurate direct correlation of histopathological changes and absorbed dose in the examined specimens.     

Metoclopramide Reduces Fluoroscopy and Procedure Time during Gastrojejunostomy Tube Placement: A Placebo-Controlled Trial

PurposeTo determine whether a single 10-mg intravenous dose of the promotility agent metoclopramide reduces the fluoroscopy time, radiation dose, and procedure time required for gastrojejunostomy (GJ) tube placement.MethodsThis prospective, randomized, double-blind, placebo-controlled trial enrolled consecutive patients who underwent primary GJ tube placement at a single institution from April 10, 2018, to October 3, 2019. Exclusion criteria included age less than 18 years, inability to obtain consent, metoclopramide allergy or contraindication, and altered pyloric anatomy. Average fluoroscopy times, radiation doses, and procedure times were compared using t-tests. The full study protocol can be found at www.clinicaltrials.gov (NCT03331965).ResultsOf 110 participants randomized 1:1, 45 received metoclopramide and 51 received placebo and underwent GJ tube placement (38 females and 58 males; mean age, 55 ± 18 years). Demographics of the metoclopramide and placebo groups were similar. The fluoroscopy time required to advance a guide wire through the pylorus averaged 1.6 minutes (range, 0.3–10.1 minutes) in the metoclopramide group versus 4.1 minutes (range, 0.2–27.3 minutes) in the placebo group (P = .002). Total procedure fluoroscopy time averaged 5.8 minutes (range, 1.5–16.2 minutes) for the metoclopramide group versus 8.8 minutes (range, 2.8–29.7 minutes) for the placebo group (P = .002). Air kerma averaged 91 mGy (range, 13–354 mGy) for the metoclopramide group versus 130 mGy (range, 24–525 mGy) for the placebo group (P = .04). Total procedure time averaged 16.4 minutes (range, 8–51 minutes) for the metoclopramide group versus 19.9 minutes (range, 6–53 minutes) for the placebo group (P = .04). There were no drug-related adverse events and no significant differences in procedure-related complications.ConclusionsA single dose of metoclopramide reduced fluoroscopy time by 34%, radiation dose by 30%, and procedure time by 17% during GJ tube placement.     

Endobronchial Navigation Guided by Cone-Beam CT–Based Augmented Fluoroscopy without a Bronchoscope: Feasibility Study in Phantom and Swine

PurposeTo evaluate the accuracy of cone-beam computed tomography (CT)-based augmented fluoroscopy (AF) image guidance for endobronchial navigation to peripheral lung targets.MethodsPrototypic endobronchial navigation AF software that superimposed segmented airways, targets, and pathways based on cone-beam CT onto fluoroscopy images was evaluated ex vivo in fixed swine lungs and in vivo in healthy swine (n = 4) without a bronchoscope. Ex vivo and in vivo (n = 3) phase 1 experiments used guide catheters and AF software version 1, whereas in vivo phase 2 (n = 1) experiments also used an endovascular steerable guiding sheath, upgraded AF software version 2, and lung-specific low-radiation-dose protocols. First-pass navigation success was defined as catheter delivery into a targeted airway segment solely using AF, with second-pass success defined as reaching the targeted segment by using updated AF image guidance based on confirmatory cone-beam CT. Secondary outcomes were navigation error, navigation time, radiation exposure, and preliminary safety.ResultsFirst-pass success was 100% (10/10) ex vivo and 19/24 (79%) and 11/15 (73%) for in vivo phases 1 and 2, respectively. Phase 2 second-pass success was 4/4 (100%). Navigation errors were 2.2 ± 1.2 mm ex vivo and 4.9 ± 3.2 mm and 4.0 ± 2.6 mm for in vivo phases 1 and 2, respectively. No major device-related complications were observed in the in vivo experiments.ConclusionsEndobronchial navigation is feasible and accurate with cone-beam CT-based AF image guidance. AF can guide endobronchial navigation with endovascular catheters and steerable guiding sheaths to peripheral lung targets, potentially overcoming limitations associated with bronchoscopy.     

CT-Guided Percutaneous Cryoablation in Patients with Lung Nodules Mainly Composed of Ground-Glass Opacities

PurposeTo assess the safety and efficacy of cryoablation in patients with lung nodules mainly composed of ground-glass opacities (GGOs).Materials and MethodsIn this retrospective study, 50 patients (mean age, 65.0 years ± 12.3; 28 women) with a diagnosis of lung GGO nodules who underwent cryoablation were included (from June 2016 to June 2021). The local recurrence rate, incidence of regional metastases to lymph nodes, incidence of distant metastases, adverse events, and lung function condition were analyzed.ResultsFollow-up computed tomography (CT) was performed at a mean of 33 months (range, 3–60 months) after the cryoablation procedure. Outcomes were only evaluated in 30 patients. A total of 20 patients were excluded. Of these 20 patients, 10 patients had no cancer detected by histopathological analysis and a diagnosis was made using CT or positron emission tomography (PET)-CT, The other 10 patients had nodules with a diameter of <10 mm and a consolidation-to-tumor ratio of >0.25; thus, histopathological analysis was not performed because of the small nodule size, and patients were diagnosed using CT or PET-CT. The local recurrence rate was 0% (0 of 30). Evidence of regional metastases of lymph nodes was not found in any patients (0%; 0 of 30), and the incidence of distant metastases was 0% (0 of 30). No major adverse events were noted. Lung function recovered to normal within 1 month after cryoablation in all patients.ConclusionsCryoablation may serve as a safe and feasible option for the treatment of lung nodules mainly composed of GGOs.     

Avoiding the Intercostal Arteries in Percutaneous Thoracic Interventions

The purpose of this study was to define relevant intercostal artery (ICA) anatomy potentially impacting the safety of thoracic percutaneous interventional procedures. An ICA abutting the upper rib and running in the subcostal groove was defined as the lowest risk zone for interventions requiring a supracostal needle puncture. A theoretical high-risk zone was defined by the ICA coursing in the lower half of the intercostal space (ICS), and a theoretical moderate-risk zone was defined by the ICA coursing below the subcostal groove but in the upper half of the ICS. Arterial phase computed tomography data from 250 patients were analyzed, revealing demographic variability, with high-risk zones extending more laterally with advancing age and with more cranial ribs. Overall, within the 97.5th percentile, an ICS puncture >7-cm lateral to the spinous process incurs moderate risk and >10-cm lateral incurs the lowest risk.     

Intravascular Ultrasound-Guided Transvenous Biopsy of Retroperitoneal Lymph Nodes: Diagnostic Accuracy and Safety Compared with CT-Guided Percutaneous Biopsy

PurposeTo compare the diagnostic accuracy and adverse event rates of intravascular ultrasound (US)-guided transvenous biopsy (TVB) versus those of computed tomography (CT)-guided percutaneous needle biopsy (PNB) for retroperitoneal (RP) lymph nodes.Materials and MethodsIn this single-institution, retrospective study, 32 intravascular US-guided TVB procedures and a sample of 34 CT-guided PNB procedures for RP lymph nodes where targets were deemed amenable to intravascular US-guided TVB were analyzed. Procedural metrics, including diagnostic accuracy, defined as diagnostic of malignancy or a clinically verifiable benign result, and adverse event rates were compared.ResultsThe targets of intravascular US-guided TVB were primarily aortocaval (47%, 15/32) or precaval (34%, 11/32), whereas those of CT-guided PNB were primarily right pericaval (44%, 15/34) or retrocaval (44%, 15/34) (P < .001). The targets of intravascular US-guided TVB averaged 2.4 cm in the long axis (range, 1.3–3.7 cm) compared with 2.9 cm (range, 1.4–5.7 cm) for those of CT-guided PNB (P = .02). There was no difference in the average number of needle passes (3.8 for intravascular US-guided TVB vs 3.9 for CT-guided PNB; P = .68). The diagnostic accuracy was 94% (30/32) and the adverse event rate was 3.1% (1/32) for intravascular US-guided TVB, similar to those of CT-guided PNB (accuracy, 91% [31/34]; adverse event rate, 2.9% [1/34]).ConclusionsIntravascular US-guided TVB had a diagnostic accuracy and adverse event rate similar to CT-guided PNB for RP lymph nodes, indicating that intravascular US-guided TVB may be as safe and effective as conventional biopsy approaches for appropriately selected targets.     

CT-Guided Percutaneous Drainage of Pneumoperitoneum Presenting as Acute Abdomen

PurposeTo evaluate the feasibility and effectiveness of computed tomography (CT)-guided percutaneous drainage (PD) in patients with iatrogenic pneumoperitoneum presenting as acute abdomen.Materials and MethodsIn this retrospective, single-center cohort study, 16 consecutive patients (9 males, 7 females; median age, 67.5 [51–85] years) undergoing PD for managing acute abdomen caused by iatrogenic pneumoperitoneum between 2013 and 2019 were analyzed. Inclusion criteria were clinical signs of acute abdomen that was unresponsive to conservative management and pneumoperitoneum due to an iatrogenic cause after PD, observed using CT imaging. Volumetry of pneumoperitoneum was performed using computer-aided image segmentation. To evaluate the clinical outcome, the paired t-test was performed to analyze the course of pain intensity on the numerical pain rating scale (NPRS, 0–10). Patient records were reviewed to determine PD-related adverse events and median drain duration.ResultsThe median pneumoperitoneum volume was 891.1 (127.7–3,677.0) mL. All PD procedures were successfully performed, with symptom relief and immediate abdominal decompression (mean segmental volume reduction, 79.8% ± 13.5). Acute abdomen symptoms were resolved, with significant improvement in pain intensity between the day of the PD procedure and the first day after the procdure (mean NPRS scores, 3.3 ± 1.9 vs 0.8 ± 1.0; P < .001). The median drain duration was 2 (1–3) days. No PD-associated adverse events were observed. After PD, 14 patients required only conservative management, whereas 2 patients with anastomotic leakage required additional surgery as they showed signs of persisting sepsis and generalized peritonitis.ConclusionsPD is a safe and suitable procedure for the management of symptoms in patients with iatrogenic pneumoperitoneum presenting as acute abdomen.     

Transcatheter CT Hepatic Arteriography Compared with Conventional CT Fluoroscopy Guidance in Percutaneous Thermal Ablation to Treat Colorectal Liver Metastases: A Single-Center Comparative Analysis of 2 Historical Cohorts

PurposeTo evaluate safety and efficacy of CT hepatic arteriography compared with conventional CT fluoroscopy guidance in percutaneous radiofrequency (RF) and microwave (MW) ablation to treat colorectal liver metastases (CRLM).Materials and MethodsThis single-center comparative, retrospective study analyzed data of 108 patients treated with 156 percutaneous ablation procedures (42 CT fluoroscopy guidance [25 RF ablation, 17 MW ablation]; 114 CT hepatic arteriography guidance [18 RF ablation, 96 MW ablation]) for 260 CRLM between January 2009 and May 2019. Local tumor progression-free survival (LTPFS) was assessed using univariate and multivariate Cox proportional hazard regression analyses. LTPFS and overall survival (OS) were estimated using the Kaplan-Meier method.ResultsThere were no complications related to the transarterial catheter procedure. CT hepatic arteriography proved superior to CT fluoroscopy regarding 2-year LTPFS (18/202 [8.9%] vs 19/58 [32.8%]; P < .001, respectively). CT hepatic arteriography versus CT fluoroscopy (hazard ratio = 0.28; 95% confidence interval, 0.15–0.54; P < .001) and MW ablation versus RF ablation (hazard ratio = 0.52; 95% confidence interval, 0.24–1.12; P = .094) were positive predictors for longer LTPFS. Multivariate analysis revealed that CT hepatic arteriography versus CT fluoroscopy (hazard ratio = 0.41; 95% confidence interval, 0.19–0.90; P = .025) was associated with a significantly superior LTPFS. OS was similar between the 2 cohorts (P = .3).ConclusionsWhile adding procedure time and marginal patient burden, transcatheter CT hepatic arteriography–guided ablation was associated with increased local disease control and superior LTPFS compared with conventional CT fluoroscopy. CT hepatic arteriography represents a safe and valid alternative to CT fluoroscopy, as it reduces the number of repeat ablations required without adding risk or detrimental effect on survival.     

Intravascular Ultrasound-Guided Transvenous Biopsy of Abdominal and Pelvic Targets Difficult to Access by Percutaneous Needle Biopsy: Technique and Initial Clinical Experience

PurposeTo report initial clinical experience with intravascular ultrasound (US)-guided transvenous biopsy (TVB) for perivascular target lesions in the abdomen and pelvis using side-viewing phased-array intracardiac echocardiography catheters.Materials and MethodsIn this single-institution, retrospective study, 48 patients underwent 50 intravascular US-guided TVB procedures for targets close to the inferior vena cava or iliac veins deemed difficult to access by conventional percutaneous needle biopsy (PNB). In all procedures, side-viewing phased-array intracardiac echocardiography intravascular US catheters and transjugular liver biopsy sets were inserted through separate jugular or femoral vein access sheaths, and 18-gauge core needle biopsy specimens were obtained under real-time intravascular US guidance. Diagnostic yield, diagnostic accuracy, and complications were analyzed.ResultsIntravascular US-guided TVB was diagnostic of malignancy in 40 of 50 procedures for a diagnostic yield of 80%. There were 5 procedures in which biopsy was correctly negative for malignancy, with a per-procedure diagnostic accuracy of 90% (45/50). Among the 5 false negatives, 2 patients underwent repeat intravascular US-guided TVB, which was diagnostic of malignancy for a per-patient diagnostic accuracy of 94% (45/48). There were 1 (2%) mild, 2 (4%) moderate, and 1 (2%) severe adverse events, with 1 moderate severity adverse event (venous thrombosis) directly attributable to the intravascular US-guided TVB technique.ConclusionsIntravascular US-guided TVB performed on difficult-to-approach perivascular targets in the abdomen and pelvis resulted in a high diagnostic accuracy, similar to accepted thresholds for PNB. Complication rates may be slightly higher but should be weighed relative to the risks of difficult PNB, surgical biopsy, or clinical management without biopsy.     

Percutaneous CT-Guided Cryoneurolysis of the Intercostobrachial Nerve for Management of Postmastectomy Pain Syndrome

PurposeTo evaluate the feasibility, safety, and efficacy of intercostobrachial nerve (ICBN) cryoneurolysis for pain control in patients with postmastectomy pain syndrome (PMPS).Materials and MethodsFourteen patients with PMPS were prospectively enrolled into this clinical trial after a positive response to a diagnostic computed tomography (CT)-guided percutaneous block of the ICBN. Participants subsequently underwent CT-guided percutaneous cryoneurolysis of the same nerve and were observed on postprocedural Days 10, 90, and 180. Pain scores, quality-of-life measurements, and global impression of change values were recorded before the procedure and at each follow-up point using established validated outcome instruments.ResultsCryoneurolysis of the ICBN was technically successful in all 14 patients. The mean pain decreased significantly by 2.1 points at 10 days (P = .0451), by 2.4 points at 90 days (P = .0084), and by 2.9 points at 180 days (P = .0028) after cryoneurolysis. Pain interference with daily activities decreased significantly by 14.4 points after 10 days (P = .0161), by 16.2 points after 90 days (P = .0071), and by 20.7 points after 180 days (P = .0007). There were no procedure-related adverse events.ConclusionsCryoneurolysis of the ICBN in patients with PMPS was technically feasible and safe and resulted in a significant decrease in postmastectomy pain for up to 6 months in this small cohort.