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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,063 records · Page 59
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

LI-RADS for CT diagnosis of hepatocellular carcinoma: performance of major and ancillary features

Purpose: To evaluate the diagnostic performance of Liver Imaging Reporting and Data System (LI-RADS) v2017 major features, the impact of ancillary features, and categories on contrast-enhanced computed tomography (CECT) for the diagnosis of hepatocellular carcinoma (HCC). Materials and methods: This retrospective study included 59 patients (104 observations including 72 HCCs) with clinical suspicion of HCC undergoing CECT between 2013 and 2016. Two radiologists independently assessed major and ancillary imaging features for each liver observation and assigned a LI-RADS category based on major features only and in combination with ancillary features. The composite reference standard included pathology or imaging. Per-lesion estimates of diagnostic performance of major features, ancillary features, and LI-RADS categories were assessed by generalized estimating equation models. Results: Major features (arterial phase hyperenhancement, washout, capsule, and threshold growth) respectively had a sensitivity of 86.1%, 81.6%, 20.7%, and 26.1% and specificity of 39.3%, 67.9%, 89.9%, and 85.0% for HCC. Ancillary features (ultrasound visibility as discrete nodule, subthreshold growth, and fat in mass more than adjacent liver) respectively had a sensitivity of 42.6%, 50.8%, and 15.1% and a specificity of 79.2%, 66.9%, and 96.4% for HCC. Ancillary features modified the final category in 4 of 104 observations. For HCC diagnosis, categories LR-3, LR-4, LR-5, and LR-TIV (tumor in vein) had a sensitivity of 5.3%, 29.0%, 53.7%, and 10.7%; and a specificity of 49.1%, 84.4%, 97.3%, and 96.4%, respectively. Conclusion: On CT, LR-5 category has near-perfect specificity for the diagnosis of HCC and ancillary features modifies the final category in few observations.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Approach to pediatric renal tumors: an imaging review

Renal tumors comprise 7% of all childhood cancers. A wide variety of renal tumors can affect the pediatric kidneys, which can be broadly classified as primary benign tumors, primary malignant tumors, and metastatic lesions. This article aims to enumerate usual benign and malignant renal tumors that can occur in childhood and emphasizes the characteristic imaging appearances which aid in their differential diagnosis. Additionally, the leading role of the Radiologist in primary diagnosis of renal infiltration by hematological malignancies and contiguous invasion by neuroblastoma is also introduced and unraveled. Imaging protocol comprises initial Ultrasound evaluation with subsequent computed tomography (CT) and/or Magnetic resonance imaging (MRI), all of which are invaluable in confirming the diagnosis, documenting the organ of origin, describing extent of local and distant spread. The complimentary role of nuclear medicine studies in delineating differential renal function, post-operative complications, and metastasis is also highlighted.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

False positives in PIRADS (V2) 3, 4, and 5 lesions: relationship with reader experience and zonal location

Purpose: To investigate the effect of reader experience and zonal location on the occurrence of false positives (FPs) in PIRADS (V2) 3, 4, and 5 lesions on multiparametric (MP)-MRI of the prostate. Materials and methods: This retrospective study included 139 patients who had consecutively undergone an MP-MRI of the prostate in combination with a transrectal ultrasound MRI fusion-guided biopsy between 2014 and 2017. MRI exams were prospectively read by a group of inexperienced radiologists (cohort 1; 54 patients) and an experienced radiologist (cohort 2; 85 patients). Multivariable logistic regression analysis was performed to determine the association of experience of the radiologist and zonal location with a FP reading. FP rates were compared between readings by inexperienced and experienced radiologists according to zonal location, using Chi-square (χ{sup 2}) tests. Results: A total of 168 lesions in 139 patients were detected. Median patient age was 68 years (Interquartile range (IQR) 62.5–73), and median PSA was 10.9 ng/mL (IQR 7.6–15.9) for the entire patient cohort. According to multivariable logistic regression, inexperience of the radiologist was significantly (P = 0.044, odds ratio 1.927, 95% confidence interval [CI] 1.017–3.651) and independently associated with a FP reading, while zonal location was not (P = 0.202, odds ratio 1.444, 95% CI 0.820–2.539). In the transition zone (TZ), the FP rate of the inexperienced radiologists 59% (17/29) was significantly higher (χ{sup 2}P = 0.033) than that of the experienced radiologist 33% (13/40). Conclusion: Inexperience of the radiologist is significantly and independently associated with a FP reading, while zonal location is not. Inexperienced radiologists have a significantly higher FP rate in the TZ.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Combination therapy of transarterial chemoembolization (TACE) and radiofrequency ablation (RFA) for small hepatocellular carcinoma: comparison with TACE or RFA monotherapy

Purpose: To compare the safety and efficacy of combined transarterial chemoembolization (TACE) and radiofrequency ablation (RFA) for small hepatocellular carcinoma (HCC) with those of TACE or RFA monotherapy. Methods: This study included 34 combined TACE and RFA (TACE-RFA), 87 TACE, and 136 ultrasound-guided RFA, which were performed to treat HCC (≤ 3 cm, 3 or fewer) between March and August 2009. The safety (Child–Pugh score indicating hepatic functional reserve, patient discomfort requiring medication, duration of hospitalization, and complications) and efficacy (1-month, 6-month, and 1-year tumor responses) profiles of each treatment were evaluated and compared. Results: TACE-RFA group showed longer hospital stay and more frequent patient discomfort requiring medication than TACE or RFA group (P < 0.001). The frequency of overall complications after TACE-RFA was higher than TACE (P = 0.006) or RFA (P = 0.009). There were no statistical differences in major complication rates between the three groups (P = 0.094). Child–Pugh score at 1-month follow-up showed no significant difference between the three groups (P = 0.162). 1-month, 6-month, and 1-year tumor responses of TACE-RFA were similar to those of RFA and better than those of TACE. Conclusions: TACE-RFA appears to result in more frequent patient discomfort requiring medication, longer hospital stay, and more frequent complications than TACE or RFA monotherapy. Tumor response of TACE-RFA seems to be similar to that of RFA and better than TACE monotherapy. Thus, TACE-RFA for treating small HCC may be required for the selected patients, especially patients with small HCC ineligible for RFA monotherapy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Anastomosing hemangioma of the liver: a case series

Purpose: To report imaging and pathologic features of five pathologically proven anastomosing hemangiomas of the liver (AHL). Methods: A retrospective review for AHL was conducted using our institutional database from 6/2004 to 3/2018. Histology proven AHL with radiologic imaging available for review were included. A total of five patients who met our criteria were identified from our institutional database. Computed tomography, ultrasound, and magnetic resonance imaging findings, including location, size, attenuation/signal intensity, enhancement characteristics, and additional imaging data were reviewed. The clinical and pathological data were also reviewed. Results: The imaging characteristics of AHL are variable, but features such as peripheral or diffuse hyperintensity on diffusion weighted imaging, arterial hyperenhancement without globular interrupted enhancement, and persistent enhancement without complete filling in the delayed phases were more characteristic of AHL. Imaging also demonstrated a lack of aggressive features. Conclusions: AHL present a diagnostic dilemma as they can mimic more malignant lesions, such as angiosarcoma, both on imaging and at pathology. While the imaging characteristics of AHL are variable, there are some features which can help distinguish AHL from other liver lesions. When the diagnosis of anastomosing hemangioma is known, the management of choice is primarily surveillance, as intervention can cause unnecessary morbidity, and no degeneration to malignancy has been identified to date.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Superior mesenteric artery syndrome: a radiographic review

Purpose: To provide a review of the etiology, clinical presentation, and imaging findings of superior mesenteric artery (SMA) syndrome. Methods: A literature review of 24 relevant articles regarding SMA syndrome was performed. Results: Clinicians and radiologists with a high index of suspicion based on symptomatology may pursue radiologic investigation in the form of upper gastrointestinal (GI) series and contrast-enhanced abdominal computed tomography (CT). Magnetic resonance imaging (MRI) and ultrasound (US) are less commonly utilized modalities in the work-up of SMA syndrome, but provide imaging alternatives without the use of ionizing radiation. Imaging can assist in diagnosis by demonstrating characteristic findings of reduced aortomesenteric angle, reduced aortomesenteric distance, gastroduodenal distention, bowel caliber narrowing at the takeoff of the superior mesenteric artery from the aorta, as well as delayed gastric emptying or positional obstruction observed with real time with fluoroscopy. Conclusion: SMA syndrome is a rare disease that can go unrecognized and undiagnosed, exacerbating weight loss in an already significantly malnourished patient population. The diagnosis of SMA syndrome must be based on clinical symptomatology correlated with radiographic information. Once diagnosed, SMA syndrome can be safely treated by conservative measures although occasionally requires invasive intervention in the form of enteral tube placement, percutaneous jejunostomy tube placement, total parenteral nutrition, ligament of Treitz lysis, or duodenojejunostomy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Traumatic Inferior Gluteal Artery Aneurysm Managed with Emergency Transcatheter Thrombin Injection

Pseudoaneurysms of the inferior gluteal artery (IGA) are rare and are often caused by trauma. Treatment options vary and include surgery, ultrasound-guided percutaneous thrombin injection, and endovascular procedures such as stent-graft placement, coil embolization, and glue injection. We report a 70-year-old male who presented to the hospital after a road accident with a posttraumatic pseudoaneurysm that was treated by endovascular thrombin embolization. To the best of our knowledge, this is the first reported case of inferior gluteal artery false aneurysm treated by this method.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Resolution of Hepatic Encephalopathy Following Hepatic Artery Embolization in a Patient with Well-Differentiated Neuroendocrine Tumor Metastatic to the Liver

Hepatic encephalopathy is considered a contraindication to hepatic artery embolization. We describe a patient with a well-differentiated neuroendocrine tumor metastatic to the liver with refractory hepatic encephalopathy and normal liver function tests. The encephalopathy was refractory to standard medical therapy with lactulose. The patient's mental status returned to baseline after three hepatic artery embolization procedures. Arteriography and ultrasound imaging before and after embolization suggest that the encephalopathy was due to arterioportal shunting causing hepatofugal portal venous flow and portosystemic shunting. In patients with a primary or metastatic well-differentiated neuroendocrine tumor whose refractory hepatic encephalopathy is due to portosystemic shunting (rather than global hepatic dysfunction secondary to tumor burden), hepatic artery embolization can be performed safely and effectively.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Central Vein Dilatation Prior to Concomitant Port Implantation

Implantation of subcutaneous port systems is routinely performed in patients requiring repeated long-term infusion therapy. Ultrasound- and fluoroscopy-guided implantation under local anesthesia is broadly established in interventional radiology and has decreased the rate of complications compared to the surgical approach. In addition, interventional radiology offers the unique possibility of simultaneous management of venous occlusion. We present a technique for recanalization of central venous occlusion and angioplasty combined with port placement in a single intervention which we performed in two patients. Surgical port placement was impossible owing to occlusion of the superior vena cava following placement of a cardiac pacemaker and occlusion of multiple central veins due to paraneoplastic coagulopathy, respectively. In both cases the affected vessel segments were dilated with balloon catheters and the port systems were placed thereafter. After successful dilatation, the venous access was secured with a 25-cm-long, 8-Fr introducer sheath, a subcutaneous pocket prepared, and the port catheter tunneled to the venipuncture site. The port catheter was introduced through the sheath with the proximal end connected to a 5-Fr catheter. This catheter was pulled through the tunnel in order to preserve the tunnel and, at the same time, allow safe removal of the long sheath over the wire. The port system functioned well in both cases. The combination of recanalization and port placement in a single intervention is a straightforward alternative for patients with central venous occlusion that can only be offered by interventional radiology.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Diagnosis of Popliteal Venous Entrapment Syndrome by Magnetic Resonance Imaging Using Blood-Pool Contrast Agents

Popliteal vascular entrapment syndrome is caused by aberrations or hypertrophy of the gastrocnemius muscles, which compress the neurovascular structures of the popliteal fossa, leading to symptoms of vascular and degeneration as well as aneurysm formation. Imaging of popliteal vascular entrapment may be performed with ultrasound, magnetic resonance imaging (MRI), computed tomography angiography, and conventional angiography. The use of blood-pool contrast agents in MRI when popliteal vascular entrapment is suspected offers the possibility to perform vascular imaging with first-pass magnetic resonance angiographic, high-resolution, steady-state imaging and allows functional tests all within one examination with a single dose of contrast agent. We present imaging findings in a case of symptomatic popliteal vein entrapment diagnosed by the use of blood pool contrast-enhanced MRI.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

A Retrospective Comparative Study of Tunneled Haemodialysis Catheters Inserted Through Occluded or Collateral Veins Versus Conventional Methods

Tunneled hemodialysis catheters become essential in dialysis access when there is no possibility of using a functioning arteriovenous fistula. Collateral or occluded veins visible on ultrasound are used for puncture and passage of catheters into the central venous system. Chronically occluded veins are crossed with guidewires to allow dilatation and subsequent passage of hemodialysis catheters. We performed a retrospective analysis of patient demographics, comorbidities, procedural complications, functional survival, performance, and history of previous vascular access. The study group was compared with two control groups in which dialysis catheters were inserted either by radiologists in the interventional suite or by clinicians on the wards. Nineteen patients from the study group were compared with same number of patients in both control groups. The mean age of the study group was higher compared with the control groups. There was no significant difference in mean functional survival, infection rates, dialysis pump speeds in the first 2 weeks, and procedural complications between the study group and the controls. The study group had a significantly higher number of previous vascular access interventions, longer dialysis careers, and more comorbidities. Tunneled dialysis catheter placement by way of collateral or occluded veins appears safe and effective. These techniques give the operator further options when faced with patients possessing challenging vascular access. Indeed, there may be a case for preferential use of these veins to keep patent central veins in reserve.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Prostatic Artery Embolization as a Primary Treatment for Benign Prostatic Hyperplasia: Preliminary Results in Two Patients

Symptomatic benign prostatic hyperplasia (BPH) typically occurs in the sixth and seventh decades, and the most frequent obstructive urinary symptoms are hesitancy, decreased urinary stream, sensation of incomplete emptying, nocturia, frequency, and urgency. Various medications, specifically 5-{alpha}-reductase inhibitors and selective {alpha}-blockers, can decrease the severity of the symptoms secondary to BPH, but prostatectomy is still considered to be the traditional method of management. We report the preliminary results for two patients with acute urinary retention due to BPH, successfully treated by prostate artery embolization (PAE). The patients were investigated using the International Prostate Symptom Score, by digital rectal examination, urodynamic testing, prostate biopsy, transrectal ultrasound (US), and magnetic resonance imaging (MRI). Uroflowmetry and postvoid residual urine volume complemented the investigation at 30, 90, and 180 days after PAE. The procedure was performed under local anesthesia; embolization of the prostate arteries was performed with a microcatheter and 300- to 500-{mu}m microspheres using complete stasis as the end point. One patient was subjected to bilateral PAE and the other to unilateral PAE; they urinated spontaneously after removal of the urethral catheter, 15 and 10 days after the procedure, respectively. At 6-month follow-up, US and MRI revealed a prostate reduction of 39.7% and 47.8%, respectively, for the bilateral PAE and 25.5 and 27.8%, respectively, for the patient submitted to unilateral PAE. The early results, at 6-month follow-up, for the two patients with BPH show a promising potential alternative for treatment with PAE.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

How to Interpret Thyroid Biopsy Results: A Three-Year Retrospective Interventional Radiology Experience

Results of thyroid biopsy determine whether thyroid nodule resection is appropriate and the extent of thyroid surgery. At our institution we use 20/22-gauge core biopsy (CBx) in conjunction with fine-needle aspiration (FNA) to decrease the number of passes and improve adequacy. Occasionally, both ultrasound (US)-guided FNA and CBx yield unsatisfactory specimens. To justify clinical recommendations for these unsatisfactory thyroid biopsies, we compare rates of malignancy at surgical resection for unsatisfactory biopsy results against definitive biopsy results. We retrospectively reviewed a database of 1979 patients who had a total of 2677 FNA and 663 CBx performed by experienced interventional radiologists under US guidance from 2003 to 2006 at a tertiary-care academic center. In 451 patients who had surgery following biopsy, Fisher's exact test was used to compare surgical malignancy rates between unsatisfactory and malignant biopsy cohorts as well as between unsatisfactory and benign biopsy cohorts. We defined statistical significance at P = 0.05. We reported an overall unsatisfactory thyroid biopsy rate of 3.7% (100/2677). A statistically significant higher rate of surgically proven malignancies was found in malignant biopsy patients compared to unsatisfactory biopsy patients (P = 0.0001). The incidence of surgically proven malignancy in unsatisfactory biopsy patients was not significantly different from that in benign biopsy patients (P = 0.8625). In conclusion, an extremely low incidence of malignancy was associated with both benign and unsatisfactory thyroid biopsy results. The difference in incidence between these two groups was not statistically significant. Therefore, patients with unsatisfactory biopsy specimens can be reassured and counseled accordingly.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Refractory Cystobiliary Fistula Secondary to Percutaneous Treatment of Hydatid Cyst: Treatment with N-Butyl 2-Cyanoacrylate Embolization

A 27-year-old female with a type 2 hydatid cystic lesion in the liver according to the Gharbi classification (CE 3A according to the WHO classification) was referred for percutaneous treatment after albendazole treatment for 1 year. A catheterization technique was performed but hypertonic saline and alcohol were not given into the cavity due to cystobiliary leakage. During the 4-month follow-up period, sequential cavitography revealed biliary fistula, and bile-stained drainage had not been ceased despite the sphincterotomy, nasobiliary drainage catheter, and plastic stent. Since the patient refused to surgery, we embolized the biliary fistula using N-butyl 2-cyanoacrylate for the first time in the literature. At the 3-month follow-up, the patient's course was uneventful and ultrasound, multidetector-row CT, and MRI examinations revealed no collection in or adjacent to the cavity.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Cryoplasty Versus Conventional Angioplasty in Femoropopliteal Arterial Recanalization: 3-Year Analysis of Reintervention-Free Survival by Treatment Received

Purpose: To compare long-term efficacy of cryoplasty therapy versus conventional angioplasty in the treatment of peripheral arterial atherosclerotic stenosis on the basis of our 3-year clinical experience. Materials and Methods: From January 2006 to December 2008, a total of 155 patients with 192 lesions of the femoropopliteal sector were randomized to receive either cryoplasty or conventional balloon angioplasty. The primary study end point was lesion target patency. Follow-up with clinical evaluation of patient's symptoms, ankle-brachial index, and Doppler ultrasound was scheduled at 1, 6, 9, 12, 24, and 36 months. Results: For the cryoplasty group (n = 86), technical immediate success was achieved in 74.4% of lesions. Rate of significant dissection was 13.5% and rate of stent placement of 22%. In the long term, target lesion patency rate at 6 months was 59.4%, with rates of 55.9, 52.6, and 49.1% at 1, 2, and 3 years, respectively. For the conventional angioplasty group (n = 69), the immediate technical success rate was 83.7%. Rate of significant dissection was 19%, and rate of stent placement was 72.9%. Patency rates at 6 months and at 1, 2, and 3 years were 71.5, 61.2, 60, and 56%, respectively. Conclusion: Compared with conventional angioplasty, cryoplasty showed good immediate success rates with lower stent placement rates. During the 3-year follow-up, patency rates tended to equalize between the two modalities.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Cardiovascular and Interventional Radiological Society of Europe Commentary on the Treatment of Chronic Cerebrospinal Venous Insufficiency

Chronic cerebrospinal venous insufficiency (CCSVI) is a putative new theory that has been suggested by some to have a direct causative relation with the symptomatology associated with multiple sclerosis (MS). The core foundation of this theory is that there is abnormal venous drainage from the brain due to outflow obstruction in the draining jugular vein and/or azygos veins. This abnormal venous drainage, which is characterised by special ultrasound criteria, called the 'venous hemodynamic insufficiency severity score' (VHISS), is said to cause intracerebral flow disturbance or outflow problems that lead to periventricular deposits. In the CCSVI theory, these deposits have a great similarity to the iron deposits seen around the veins in the legs in patients with chronic deep vein thrombosis. Zamboni, who first described this new theory, has promoted balloon dilatation to treat the outflow problems, thereby curing CCSVI and by the same token alleviating MS complaints. However, this theory does not fit into the existing bulk of scientific data concerning the pathophysiology of MS. In contrast, there is increasing worldwide acceptance of CCSVI and the associated balloon dilatation treatment, even though there is no supporting scientific evidence. Furthermore, most of the information we have comes from one source only. The treatment is called 'liberation treatment,' and the results of the treatment can be watched on YouTube. There are well-documented testimonies by MS patients who have gained improvement in their personal quality of life (QOL) after treatment. However, there are no data available from patients who underwent unsuccessful treatments with which to obtain a more balanced view. The current forum for the reporting of success in treating CCSVI and thus MS seems to be the Internet. At the CIRCE office and the MS Centre in Amsterdam, we receive approximately 10 to 20 inquiries a month about this treatment. In addition, many interventional radiologists, who are directly approached by MS patients, contact the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) for advice. Worldwide, several centres are actively promoting and performing balloon dilatation, with or without stenting, for CCSVI. Thus far, no trial data are available, and there is currently no randomized controlled trial (RCT) in progress Therefore, the basis for this new treatment rests on anecdotal evidence and successful testimonies by patients on the Internet. CIRSE believes that this is not a sound basis on which to offer a new treatment, which could have possible procedure-related complications, to an often desperate patient population.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Devascularization of Head and Neck Paragangliomas by Direct Percutaneous Embolization

Preoperative transarterial embolization of head and neck paragangliomas using particulate agents has proven beneficial for decreasing intraoperative blood loss. However, the procedure is often incomplete owing to extensive vascular structure and arteriovenous shunts. We report our experience with embolization of these lesions by means of direct puncture and intratumoral injection of n-butyl cyanoacrylate (NBCA) or Onyx. Ten patients aged 32-82 years who were referred for preoperative embolization of seven carotid body tumors and three jugular paragangliomas were retrospectively analyzed. Intratumoral injections were primarily performed in four cases with multiple small-caliber arterial feeders and adjunctive to transarterial embolization in six cases with incomplete devascularization. Punctures were performed under ultrasound and injections were performed under roadmap fluoroscopic guidance. Detailed angiographies were performed before and after embolization procedures. Control angiograms showed complete or near-complete devascularization in all tumors. Three tumors with multiple small-caliber arterial feeders were treated with primary NBCA injections. One tumor necessitated transarterial embolization after primary injection of Onyx. Six tumors showed regional vascularization from the vasa vasorum or small-caliber branches of the external carotid artery following the transarterial approach. These regions were embolized with NBCA injections. No technical or clinical complications related to embolization procedures occurred. All except one of the tumors were surgically removed following embolization. In conclusion, preoperative devascularization with percutaneous direct injection of NBCA or Onyx is feasible, safe, and effective in head and neck paragangliomas with multiple small-caliber arterial feeders and in cases of incomplete devascularization following transarterial embolization.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Percutaneous Endovascular Treatment of Hepatic Artery Stenosis in Adult and Pediatric Patients After Liver Transplantation

The purpose of this study was to evaluate the efficacy of percutaneous endovascular techniques for the treatment of hepatic artery stenosis (HAS) occurring after liver transplantation (LT) in adult and pediatrics patients. From February 2003 to March 2009, 25 patients (15 adults and 10 children) whose developed HAS after LT were referred to our interventional radiology unit. Technical success was achieved in 96% (24 of 25) of patients. Percutaneous transluminal angioplasty (PTA) was performed in 13 patients (7 children), and stenting was performed in 11 patients (2 children). After the procedure, all patients were followed-up with liver function tests, Doppler ultrasound, and/or computed tomography. Mean follow-up was 15.8 months (range 5 days to 58 months). Acute hepatic artery thrombosis occurred immediately after stent deployment in 2 patients and was successfully treated with local thrombolysis. One patient developed severe HA spasm, which reverted after 24 h. After the procedure, mean trans-stenotic pressure gradient decreased from 30.5 to 6.2 mmHg. Kaplan-Meyer curve of HA primary patency was 77% at 1 and 2 years. During the follow-up period, 5 patients (20%) had recurrent stenosis, and 2 patients (8.3%) had late thrombosis. Two of 7 patients with stenosis/thrombosis underwent surgical revascularization (n = 1) and liver retransplantation (n = 1). Six (25%) patients died during follow-up, but overall mortality was not significantly different when comparing patients having patent hepatic arteries with those having recurrent stenosis/thrombosis. There were no significant differences in recurrent stenosis/thrombosis and mortality comparing patients treated by PTA versus stenting and comparing adult versus pediatric status. Percutaneous interventional treatment of HAS in LT recipients is safe and effective and decreases the need for surgical revascularization and liver retransplantation. However, the beneficial effects for survival are not clear, probably because the clinical complexity of many of these cases.

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