Aggressive Management of a Bilateral Chylothorax Complicating an Orthotopic Heart-Kidney Transplantation.

Chylothorax after an orthotopic heart transplant is a rare but potentially detrimental occurrence. This is the first reported case of bilateral chylothorax complicating a heart-kidney transplant patient. No universally accepted protocol exists for the management of chylothorax in general population, let alone the immunocompromised transplant patient. This case presents unique challenges to the management of postoperative chylothorax given heart-kidney transplant's effect on the patient's volume status and immunocompromised state. We make the argument for aggressive treatment of chylothorax in an immunocompromised heart-kidney transplant patient to limit complications in a patient population predisposed to infection.

Evaluating the Performance of a Commercially Available Artificial Intelligence Algorithm for Automated Detection of Pulmonary Embolism on Contrast-Enhanced Computed Tomography and Computed Tomography Pulmonary Angiography in Patients With Coronavirus Disease 2019.

Objective: To investigate the performance of a commercially available artificial intelligence (AI) algorithm for the detection of pulmonary embolism (PE) on contrast-enhanced computed tomography (CT) scans in patients hospitalized for coronavirus disease 2019 (COVID-19). Patients and Methods: Retrospective analysis was performed of all contrast-enhanced chest CT scans of patients admitted for COVID-19 between March 1, 2020 and December 31, 2021. Based on the original radiology reports, all PE-positive examinations were included (n=527). Using a reversed-flow single-gate diagnostic accuracy case-control model, a randomly selected cohort of PE-negative examinations (n=977) was included. Pulmonary parenchymal disease severity was assessed for all the included studies using a semiquantitative system, the total severity score. All included CT scans were sent for interpretation by the commercially available AI algorithm, Aidoc. Discrepancies between AI and original radiology reports were resolved by 3 blinded radiologists, who rendered a final determination of indeterminate, positive, or negative. Results: A total of 78 studies were found to be discrepant, of which 13 (16.6%) were deemed indeterminate by readers and were excluded. The sensitivity and specificity of AI were 93.2% (95% CI, 90.6%-95.2%) and 99.6% (95% CI, 98.9%-99.9%), respectively. The accuracy of AI for all total severity score groups (mild, moderate, and severe) was high (98.4%, 96.7%, and 97.2%, respectively). Artificial intelligence was more accurate in PE detection on CT pulmonary angiography scans than on contrast-enhanced CT scans (P<.001), with an optimal Hounsfield unit of 362 (P=.048). Conclusion: The AI algorithm demonstrated high sensitivity, specificity, and accuracy for PE on contrast-enhanced CT scans in patients with COVID-19 regardless of parenchymal disease. Accuracy was significantly affected by the mean attenuation of the pulmonary vasculature. How this affects the legitimacy of the binary outcomes reported by AI is not yet known.

Aggressive Management of a Bilateral Chylothorax Complicating an Orthotopic Heart-Kidney Transplantation

ABSTRACT Chylothorax after an orthotopic heart transplant is a rare but potentially detrimental occurrence. This is the first reported case of bilateral chylothorax complicating a heart-kidney transplant patient. No universally accepted protocol exists for the management of chylothorax in general population, let alone the immunocompromised transplant patient. This case presents unique challenges to the management of postoperative chylothorax given heart-kidney transplant's effect on the patient's volume status and immunocompromised state. We make the argument for aggressive treatment of chylothorax in an immunocompromised heart-kidney transplant patient to limit complications in a patient population predisposed to infection.

Work-Up of Lower Extremity Swelling in a Patient With Ehlers-Danlos Syndrome.

A 36-year-old woman with Ehlers-Danlos syndrome (EDS) presents with a painful and enlarging right lower extremity mass prompting imaging work up. Herein we present a case report of an uncommon complication and a unique treatment option of a large right anterior tibial artery pseudoaneurysm caused by repetitive microtrauma in a patient with EDS and a congenital club foot.

Hepatocellular carcinoma radiation segmentectomy treatment intensification prior to liver transplantation increases rates of complete pathologic necrosis: an explant analysis of 75 tumors.

PURPOSE: To verify the correlation between yttrium-90 glass microsphere radiation segmentectomy treatment intensification of hepatocellular carcinoma (HCC) and complete pathologic necrosis (CPN) at liver transplantation. METHODS: A retrospective, single center, analysis of patients with HCC who received radiation segmentectomy prior to liver transplantation from 2016 to 2021 was performed. The tumor treatment intensification cohort (n = 38) was prescribed radiation segmentectomy as per response recommendations identified in a previously published baseline cohort study (n = 37). Treatment intensification and baseline cohort treatment parameters were compared for rates of CPN. Both cohorts were then combined for an overall analysis of treatment parameter correlation with CPN. RESULTS: Sixty-three patients with a combined 75 tumors were analyzed. Specific activity, dose, and treatment activity were significantly higher in the treatment intensification cohort (all p < 0.01), while particles per cubic centimeter of treated liver were not. CPN was achieved in 76% (n = 29) of tumors in the treatment intensification cohort compared to 49% (n = 18) in the baseline cohort (p = 0.013). The combined cohort CPN rate was 63% (n = 47). ROC analysis showed that specific activity ≥ 327 Bq (AUC 0.75, p < 0.001), dose ≥ 446 Gy (AUC 0.69, p = 0.005), and treatment activity ≥ 2.55 Gbq (AUC 0.71, p = 0.002) were predictive of CPN. Multivariate logistic regression demonstrated that a specific activity ≥ 327 Bq was the sole independent predictor of CPN (p = 0.013). CONCLUSION: Radiation segmentectomy treatment intensification for patients with HCC prior to liver transplantation increases rates of CPN. While dose strongly correlated with pathologic response, specific activity was the most significant independent radiation segmentectomy treatment parameter associated with CPN.

Radiation Segmentectomy for the Treatment of Solitary Hepatocellular Carcinoma: Outcomes Compared with Those of Surgical Resection.

PURPOSE: To investigate the outcomes of radiation segmentectomy (RS) versus standard-of-care surgical resection (SR). MATERIALS AND METHODS: A multisite, retrospective analysis of treatment-naïve patients who underwent either RS or SR was performed. The inclusion criteria were solitary hepatocellular carcinoma ≤8 cm in size, Eastern Cooperative Oncology Cohort performance status of 0-1, and absence of macrovascular invasion or extrahepatic disease. Target tumor and overall progression, time to progression (TTP), and overall survival rates were assessed. Outcomes were censored for liver transplantation. RESULTS: A total of 123 patients were included (RS, 57; SR, 66). Tumor size, Child-Pugh class, albumin-bilirubin score, platelet count, and fibrosis stage were significantly different between cohorts (P ≤ .01). Major adverse events (AEs), defined as grade ≥3 per the Clavien-Dindo classification, occurred in 0 patients in the RS cohort vs 13 (20%) patients in the SR cohort (P < .001). Target tumor progression occurred in 3 (5%) patients who underwent RS and 5 (8%) patients who underwent SR. Overall progression occurred in 19 (33%) patients who underwent RS and 21 (32%) patients who underwent SR. The median overall TTP was 21.9 and 29.4 months after RS and SR, respectively (95% confidence interval [CI], 15.5-28.2 and 18.5-40.3, respectively; P = .03). Overall TTP subgroup analyses showed no difference between treatment cohorts with fibrosis stages 3-4 (P = .26) and a platelet count of <150 × 109/L (P = .29). The overall progression hazard ratio for RS versus SR was not significant per the multivariate Cox regression analysis (1.16; 95% CI, 0.51-2.63; P = .71). The median overall survival was not reached for either of the cohorts. Propensity scores were calculated but were too dissimilar for analysis. CONCLUSIONS: RS and SR were performed in different patient populations, which limits comparison. RS approached SR outcomes, with a lower incidence of major AEs, in patients who were not eligible for hepatectomy.

Resolution of acute pulmonary embolism using anticoagulation therapy alone in coronavirus disease 2019.

OBJECTIVE: To investigate the radiographic resolution of acute pulmonary embolism (PE) using contrast-enhanced computed tomography (CECT) examinations in patients diagnosed with acute PE while hospitalized with coronavirus disease 2019 (COVID-19) and to understand the mid-term and long-term implications of anticoagulation therapy. METHODS: We identified patients with acute PE per CECT and at least one follow-up CECT from March 11, 2020, to May 27, 2021, using a prospective registry of all hospitalized patients with COVID-19 infection receiving care within a multicenter Health System. Initial and follow-up CECT examinations were reviewed independently by two radiologists to evaluate for PE resolution. The Modified Miller Score was used to assess for thrombus burden at diagnosis and on follow-up. RESULTS: Of the 6070 hospitalized patients with COVID-19 infection, 5.7% (348/6070) were diagnosed with acute PE and 13.5% (47/348) had a follow-up CECT examination. The mean ± standard deviation time to follow-up imaging was 44 ± 48 days (range, 3-161 days). Of 47 patients, 47 (72.3%) had radiographic resolution of PE, with a mean time to follow-up of 48 ± 43 days (range, 6-239 days). All patients received anticoagulation monotherapy for a mean of 149 ± 95 days and this included apixaban (63.8%), warfarin (12.8%), and rivaroxaban (8.5%), among others. The mean Modified Miller Score at PE diagnosis and follow-up was 4.8 ± 4.2 (range, 1-14) and 1.4 ± 3.3 (range, 0-16; P < .0001), respectively. Nine patients (19%) died at a mean of 13 ± 8 days after follow-up CECT (range, 1-27 days) and at a mean of 28 ± 16 days after admission (range, 11-68 days). Seen of the nine deaths (78%) deaths were associated with progression of COVID-19 pneumonia. CONCLUSIONS: Hospitalized patients with COVID-19 have a clinically apparent 5.7% rate of developing PE. In patients with follow-up imaging, 72.3% had radiographic thrombus resolution at a mean of 44 days while on anticoagulation. Prospective studies of the natural history of PEs with COVID-19 that include systematic follow-up imaging are warranted to help guide anticoagulation recommendations.

Myelopathy after traumatic lumbar vertebral intraosseous arteriovenous fistula with epidural venous drainage treated with transvenous embolization.

Spinal epidural arteriovenous fistulas are an uncommon entity. The authors present an interesting case of a 48-year-old man involved in a MVC five months prior to presenting with bilateral lower extremity weakness and hypoesthesia below the knees. MRI demonstrated a flow void in the L1 vertebral body burst fracture along with a dilated basivertebral vein draining in to engorged epidural venous plexus. Angiography confirmed an intraosseous arteriovenous fistula fed by T12 and L1arteries and epidural venous drainage. Complete obliteration by arterial embolization was precluded by origin of the artery of Adamkiewicz from the feeding L1 lumbar artery. Embolization using a transvenous approach allowed for successful obliteration of the fistula. Following the procedure, the patient had significant immediate improvement in the lower extremity symptoms. This is the first report of a posttraumatic spinal epidural arteriovenous fistula secondary to a vertebral burst fracture successfully treated by transvenous embolization.

Biochemical Safety of Ablative Yttrium-90 Radioembolization for Hepatocellular Carcinoma as a Function of Percent Liver Treated.

PURPOSE: Transarterial radioembolization can serve as an ablative therapy for early-stage hepatocellular carcinoma (HCC). Given the volumetric variability of liver segments, this study aimed to characterize the safety of ablative radioembolization by determining percent liver treated (%LT) thresholds associated with biochemical toxicity. PATIENTS AND METHODS: Patients with HCC receiving a single ablative radioembolization treatment using glass microspheres from 2017 through 2020 were reviewed. %LT was calculated as treatment angiosome volume divided by whole liver volume. Biochemical toxicities were defined as increases in Albumin-Bilirubin (ALBI) grade or Child-Pugh (CP) class compared to baseline and albumin or bilirubin adverse events (AEs) per the Common Terminology Criteria for Adverse Events. Receiver operating characteristic curves and multivariate logistic regression analyses were performed to assess the impact of %LT on toxicities. RESULTS: Of 141 patients analyzed, 53% (n=75) were ALBI 1, 45% (n=64) ALBI 2, 79% (n=111) CP-A, and 21% (n=30) CP-B. A %LT ≥14.5% was associated with grade/class increases in ALBI 2 (p≤0.01) and CP-B patients (p=0.026). In multivariate analysis, a %LT ≥14.5% was an independent predictor of increases in the ALBI 2 and CP-B groups (p<0.01). No significant %LT threshold was found for ALBI 1 and CP-A patients. No grade 3/4 albumin or bilirubin AEs were reported, while grade 2 AEs were related to an initial whole liver volume <1.3 L (p≤0.01). CONCLUSION: Patients with ALBI 2 and CP-B liver function are less likely to have an increase in their respective grade/class when treating <14.5% of the liver using glass microspheres. ALBI 1 and CP-A patients showed no definitive %LT threshold for biochemical toxicity within the range of this study.

Iliocaval reconstruction of chronically thrombosed cylindrical inferior vena cava filters with balloon expandable covered stent-grafts.

The use of a Viabahn VBX endoprosthesis (W. L. Gore & Associates, Flagstaff, Ariz) to exclude chronically thrombosed inferior vena cava (IVC) filters refractory to exclusion with self-expanding stents was evaluated. The mean duration of TrapEase IVC (Cordis, Milpitas, Calif) implantation was 7.6 years (range, 2-11 years). Symptoms included leg pain, edema, color changes, and back pain. The mean Villalta score and venous clinical severity score were 17 (range, 13-23) and 13 (range, 11-15), respectively. Indirect ultrasound evidence of stent patency was demonstrated at a mean of 8 months after intervention. The mean Villalta score and venous clinical severity score had decreased by 13 and 10, respectively, at a mean of 9.5 months after intervention. Iliocaval reconstruction with Viabahn VBX balloon expandable stent-graft exclusion of chronically thrombosed TrapEase IVC filters is safe, with favorable short-term results.

Natural History of Incidental Enhancing Nodules on Cone-Beam Computed Tomography during Transarterial Therapy of Hepatocellular Carcinoma.

PURPOSE: To evaluate the natural history of incidental enhancing nodules (IENs) on contrast-enhanced cone-beam computed tomography (CT) during transarterial treatment of hepatocellular carcinoma (HCC). MATERIAL AND METHODS: A single-center retrospective analysis of 100 patients with HCC who underwent contrast-enhanced cone-beam CT prior to transarterial treatment from August 2015 to June 2019 was performed. Inclusion criteria were patients with segmental distribution sublobar HCC, contrast-enhanced cone-beam CT of the target lesion and nontarget liver parenchyma, and follow-up cross-sectional imaging. Patients with IENs ≥3 mm that did not meet imaging criteria for HCC were analyzed. Exclusion criteria included biphenotypic tumors and IEN present inside the treated area of the liver. RESULTS: Fifty-six patients demonstrated 154 IENs on contrast-enhanced cone-beam CT, of which 13 IENs (8.5%) progressed to HCC. The mean primary tumor size was 29 mm (range: 10.2-189 mm). Ten patients had ≥4 IENs, and 46 patients had 1-3 IENs. The mean IEN size was 6.8 mm (range: 3.0-16.3 mm). The median follow-up interval after contrast-enhanced cone-beam CT was 282 days (interquartile range: 143-522). Increased alpha-fetoprotein before treatment (≥15.5 ng/mL, P = .035), having ≥4 IENs (P = .020), and hepatitis C virus (P = .015) were significantly correlated with IEN progression to HCC. No statistically significant differences were identified in baseline neutrophil-to-lymphocyte ratio, targeted HCC characteristics (size, macrovascular invasion, infiltrative pattern, enhancement pattern, and satellite lesions), and IEN size between those with IEN progression to HCC and those without. CONCLUSIONS: Most IENs of ≥3 mm on contrast-enhanced cone-beam CT in patients with segmental distribution sublobar HCC do not progress to HCC. Patients with segmental distribution sublobar HCC with ≥4 IENs, alpha-fetoprotein elevation (≥15.5 ng/mL), or hepatitis C virus have an increased risk of IEN progression to HCC.

Pathologic Response of Hepatocellular Carcinoma Treated with Yttrium-90 Glass Microsphere Radiation Segmentectomy Prior to Liver Transplantation: A Validation Study.

PURPOSE: To evaluate the pathologic outcomes of hepatocellular carcinoma (HCC) treated with Yttrium-90 radiation segmentectomy using glass microspheres prior to liver transplantation and explore parameters associated with pathologic necrosis. MATERIALS AND METHODS: A single-institution retrospective analysis of HCC patients who received radiation segmentectomy prior to liver transplantation from November 2016 to May 2020 was performed. Patients were included if the treatment angiosome encompassed the entire tumor and could be correlated with available gross pathology. Archived histology slides were reviewed for percentage of pathologic necrosis. Thirty-three patients with 37 tumors were evaluated. The median tumor size was 2.3 cm (range, 1-6.7 cm). RESULTS: All tumors received a single treatment. The median time from radiation segmentectomy to transplantation was 206 days (range, 58-550 days). Objective response per Modified Response Evaluation Criteria in Solid Tumors (mRECIST) was 92% (complete response, 76%; partial response, 16%). A total of 68% (n = 25) of tumors demonstrated ≥99% pathologic necrosis. Complete pathologic necrosis was present in 53% and 75% of tumors treated with >190 Gy (n = 18) and >500 Gy (n = 8) single-compartment Medical Internal Radiation Dose, respectively. Complete response per mRECIST, posttreatment angiosome T1 hypointensity, dose >190 Gy, microsphere specific activity >297 Bq, and a longer time between treatment and transplant were associated with ≥99% tumor necrosis (P < .05). No posttransplant tumor recurrences occurred within a median follow-up of 604 days (range, 138-1,223 days). CONCLUSIONS: Radiation segmentectomy can serve as an ablative modality for the treatment of HCC prior to liver transplant.

Extraspinal Vascular Malformation with Retrograde Drainage through a Radicular Vein: Treatment with Percutaneous Transgluteal Embolization.

BACKGROUND: Spinal arteriovenous fistulas have abnormal connections between spinal arteries and veins. Early diagnosis and management are essential for preventing permanent neurologic deficits. Although symptoms of myelopathy are commonly related to established types of spinal arteriovenous fistulas within the spine, extraspinal arteriovenous anomalies may also result in similar pathology and pose challenges to conventional endovascular treatment. CASE DESCRIPTION: A 61-year-old man presented with progressive weakness and decreasing sensation in the lower extremities. He had a remote history of craniopharyngioma surgery and deep venous thrombosis. Examination showed decreased strength and reflexes in the lower extremities. Magnetic resonance imaging demonstrated T2 cord signal changes and flow voids within the spinal canal. Angiogram showed bilateral internal iliac artery arteriovenous malformations with retrograde flow into a radicular vein and venous congestion of the medullary veins. Percutaneous transgluteal puncture of the superior gluteal vein was performed, and the abnormal inflow to the radicular vein was obliterated with coiling and Onyx embolization. The patient had significant clinical improvement, and follow-up imaging demonstrated resolution of T2 cord signal changes and flow voids. CONCLUSIONS: Extraspinal vascular malformations with vascular myelopathy are extremely rare. They include a broad spectrum of complex vascular disorders and often require alternate endovascular approaches.

Transchondral access for irreversible electroporation of hepatocellular carcinoma.

Ablative treatment for hepatocellular carcinoma is standard of care in selected settings and is endorsed by international societal guidelines. Centrally located hepatocellular carcinoma are difficult to treat due to their proximity to vasculature and central bile ducts. Irreversible electroporation is a nonthermal ablation modality that has been shown to preserve the extracellular matrix and is less likely to damage structures such as bile ducts and is not susceptible to vascular heat sink. Successful irreversible electroporation requires the parallel placement of probes which can be prevented by ribs or the sternum. This case report describes the use of the coaxial bone biopsy system to enable transchondral access and facilitate parallel placement of probes during irreversible electroporation IRE for the treatment of hepatocellular carcinoma.

Radiofrequency Ablation, Where It Stands in Interventional Radiology Today.

Radiofrequency ablation (RFA) is one of the first developed minimally invasive definitive cancer therapies. The safety and efficacy of RFA is well documented and has led to its incorporation into multiple international societal guidelines. By expanding on the body of knowledge acquired during the clinical use of RFA, alternative ablative technologies have emerged and are successfully competing for locoregional therapy market share. The adaption of newer ablative technologies is leading to a rapid decline in the utilization of RFA by interventional radiologists despite the lack of proven superiority. In their 2010 article, Hong and Georgiades stated "… RFA is likely to remain the mainstay of ablations for small tumors until sufficient experience emerges for the widespread acceptance for alternative ablative modalities." Within a decade of this publication, has this time arrived?

Renal artery injury during inferior vena cava filter removal with endobronchial forceps.

Retrieval of tip-embedded inferior vena cava filters using endobronchial forceps is a well-described technique. The tip of dorsally tilted filters may be in proximity to the right renal artery, increasing the risk of arterial injury during retrieval. We present one case that illustrates renal artery injury requiring emergent stent graft repair. The three subsequent cases illustrate techniques that avoid renal artery injury using a femoral and jugular approach with the assistance of an arterial fiducial wire. Renal artery injury is a potential complication during retrieval of filters using endobronchial forceps that can be prevented with careful planning.

Occurrence of angiographic femoral artery complications after vascular closure with Mynx and AngioSeal.

INTRODUCTION: There have been recent reports of high vascular complication rates after the use of the Mynx vascular closure device (VCD). At our institution, vascular complications due to these devices have rarely been encountered. A study was undertaken to retrospectively compare angiographic abnormalities seen after femoral artery closure by both the Mynx and AngioSeal VCDs to provide further insight into the risks associated with VCDs. METHODS: All adult patients who underwent deployment of either a Mynx or AngioSeal VCD and subsequently underwent repeat angiography within the next 30 days between 1 July 2010 and 1 April 2011 were reviewed. Two independent blinded radiologists compared blinded pre-procedure and follow-up femoral angiograms for the presence of pseudoaneurysm or other vascular abnormality. Hospital records were reviewed for major or minor complications of the groin site or femoral artery. RESULTS: Thirty patients (31 angiograms) underwent vascular closure with a Mynx and 57 patients (69 angiograms) received an AngioSeal. The average time elapse until repeat femoral angiography was 6.2 days (range 1-21, median 5.5 days) in the Mynx group and 6.3 days (range 0-30, median 5 days) in the AngioSeal group. Two pseudoaneurysms and one minor stenosis were identified in the AngioSeal group. No angiographic abnormalities were seen in the Mynx group. No intraluminal filling defects were demonstrated on any of the follow-up femoral angiograms. One patient who received an AngioSeal developed a delayed minor groin site hematoma that did not require surgical intervention. CONCLUSIONS: Angiographic complications were seen in only 3% of patients after closure with Mynx or AngioSeal VCDs. There were no clinically significant groin site or vascular complications. These data suggest that both VCDs are safe for use after angiography with a low rate of femoral artery complications.