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1.
Eur J Nucl Med Mol Imaging ; 50(13): 3826-3837, 2023 11.
Article in English | MEDLINE | ID: mdl-37540237

ABSTRACT

BACKGROUND: Cancer is a leading cause of death worldwide. While routine diagnosis of cancer is performed mainly with biopsy sampling, it is suboptimal to accurately characterize tumor heterogeneity. Positron emission tomography (PET)-driven radiomic research has demonstrated promising results when predicting clinical endpoints. This study aimed to investigate the added value of quantum machine learning both in simulator and in real quantum computers utilizing error mitigation techniques to predict clinical endpoints in various PET cancer patients. METHODS: Previously published PET radiomics datasets including 11C-MET PET glioma, 68GA-PSMA-11 PET prostate and lung 18F-FDG PET with 3-year survival, low-vs-high Gleason risk and 2-year survival as clinical endpoints respectively were utilized in this study. Redundancy reduction with 0.7, 0.8, and 0.9 Spearman rank thresholds (SRT), followed by selecting 8 and 16 features from all cohorts, was performed, resulting in 18 dataset variants. Quantum advantage was estimated by Geometric Difference (GDQ) score in each dataset variant. Five classic machine learning (CML) and their quantum versions (QML) were trained and tested in simulator environments across the dataset variants. Quantum circuit optimization and error mitigation were performed, followed by training and testing selected QML methods on the 21-qubit IonQ Aria quantum computer. Predictive performances were estimated by test balanced accuracy (BACC) values. RESULTS: On average, QML outperformed CML in simulator environments with 16-features (BACC 70% and 69%, respectively), while with 8-features, CML outperformed QML with + 1%. The highest average QML advantage was + 4%. The GDQ scores were ≤ 1.0 in all the 8-feature cases, while they were > 1.0 when QML outperformed CML in 9 out of 11 cases. The test BACC of selected QML methods and datasets in the IonQ device without error mitigation (EM) were 69.94% BACC, while EM increased test BACC to 75.66% (76.77% in noiseless simulators). CONCLUSIONS: We demonstrated that with error mitigation, quantum advantage can be achieved in real existing quantum computers when predicting clinical endpoints in clinically relevant PET cancer cohorts. Quantum advantage can already be achieved in simulator environments in these cohorts when relying on QML.


Subject(s)
Fluorodeoxyglucose F18 , Lung Neoplasms , Male , Humans , Positron-Emission Tomography/methods , Lung Neoplasms/pathology , Lung/pathology , Computers , Positron Emission Tomography Computed Tomography/methods , Retrospective Studies
2.
Sci Rep ; 12(1): 1851, 2022 02 03.
Article in English | MEDLINE | ID: mdl-35115630

ABSTRACT

Quantum machine learning has experienced significant progress in both software and hardware development in the recent years and has emerged as an applicable area of near-term quantum computers. In this work, we investigate the feasibility of utilizing quantum machine learning (QML) on real clinical datasets. We propose two QML algorithms for data classification on IBM quantum hardware: a quantum distance classifier (qDS) and a simplified quantum-kernel support vector machine (sqKSVM). We utilize these different methods using the linear time quantum data encoding technique ([Formula: see text]) for embedding classical data into quantum states and estimating the inner product on the 15-qubit IBMQ Melbourne quantum computer. We match the predictive performance of our QML approaches with prior QML methods and with their classical counterpart algorithms for three open-access clinical datasets. Our results imply that the qDS in small sample and feature count datasets outperforms kernel-based methods. In contrast, quantum kernel approaches outperform qDS in high sample and feature count datasets. We demonstrate that the [Formula: see text] encoding increases predictive performance with up to + 2% area under the receiver operator characteristics curve across all quantum machine learning approaches, thus, making it ideal for machine learning tasks executed in Noisy Intermediate Scale Quantum computers.

3.
BJS Open ; 5(5)2021 09 06.
Article in English | MEDLINE | ID: mdl-34498667

ABSTRACT

BACKGROUND: In adults, intussusception has been considered traditionally to have an underlying aetiology. The aim of this study was to determine CT and clinical features of small-bowel intussusceptions that required surgical intervention. METHODS: Adult patients were identified in whom small-bowel intussusceptions were noted on CT images. The appearance, number, type (enteroenteric versus enterocolic), length and maximum short-axis diameter of intussusceptions, and presence of bowel obstruction (short-axis diameter of proximal small bowel greater than 3 cm) were analysed. The outcome was defined as surgical (complicated) or self-limiting (uncomplicated). Associations between complicated and uncomplicated intussusceptions and patient characteristics were investigated. RESULTS: Among 75 patients (56 male) with a mean age of 45 years, 103 intussusceptions were identified, of which 98 (95 per cent) were enteroenteric and 5 (5 per cent) enterocolic. Only 12 of 103 intussusceptions (12 per cent) in 12 of 75 (16 per cent) patients required surgical therapy and were considered to be complicated, with half of these having a neoplastic lead point. Length (P < 0.001), diameter (P < 0.001) and type (P = 0.002) of intussusception as well as presence of vessels (P = 0.023) within an intussusception on a CT scan, clinical symptoms (P = 0.007) and signs of bowel obstruction (P < 0.001) were associated with a surgical outcome. CONCLUSION: Clinical symptoms, signs of bowel obstruction, type and length of intussusception, and a visible tumour within an intussusception on CT scan were critical signs of complicated intussusception, requiring surgical intervention.


Subject(s)
Intussusception , Abdomen , Adult , Humans , Intestine, Small/diagnostic imaging , Intestine, Small/surgery , Intussusception/diagnostic imaging , Intussusception/surgery , Male , Middle Aged , Tomography, X-Ray Computed
4.
Cardiovasc Intervent Radiol ; 42(12): 1687-1694, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31531691

ABSTRACT

PURPOSE: To evaluate the incidence of acute renal failure and chronic kidney disease due to occlusion of accessory renal arteries during endovascular aneurysm repair of infrarenal abdominal aortic aneurysm. MATERIAL AND METHODS: We retrospectively reviewed the course of 181 patients (mean age, 71, SD ± 9  years) who underwent EVAR of infrarenal abdominal aortic aneurysm. The renal vessel anatomy was analyzed in all pre- and postoperative CT scans. Diameter and origin of accessory renal arteries were evaluated. Renal function was determined by pre- and postoperative serum creatinine and eGFR levels. Long-term follow-up (>3 months) of patients was available in 121 cases (66.9%). Acute kidney injury and chronic kidney failure were defined according to guidelines of "Kidney Disease: Improving Global Outcomes" (KDIGO). RESULTS: In 65 of 181 patients (33.9%), 82 accessory renal arteries were identified preoperatively. In 19 of 181 patients (10.5%), one or more accessory renal arteries were covered and subsequently occluded by the implanted stent-graft device. Neither acute kidney injury (10.3% vs 12.5%; p = .785) nor chronic kidney disease (10.7% vs 15.38%; p = .452) was detected significantly more often in patients with covered accessory renal artery. The only significant predictor of acute kidney injury was the preoperative serum creatinine level (1.12 mg/dl vs. 0.98 mg/dl; p = .03). Significant predictors for chronic kidney disease were preoperative serum creatinine, eGFR, and impaired renal function (p < .001). CONCLUSION: Coverage of accessory renal artery due to stent-graft does not lead either to temporary acute kidney injury after endovascular aneurysm repair or to chronic kidney disease. LEVEL OF EVIDENCE: Level II b.


Subject(s)
Acute Kidney Injury/epidemiology , Aortic Aneurysm, Abdominal/surgery , Blood Vessel Prosthesis Implantation/methods , Postoperative Complications/epidemiology , Renal Artery/surgery , Renal Insufficiency, Chronic/epidemiology , Aged , Aortic Aneurysm, Abdominal/epidemiology , Endovascular Procedures/methods , Female , Follow-Up Studies , Humans , Male , Retrospective Studies , Treatment Outcome
5.
Cardiovasc Intervent Radiol ; 42(2): 213-219, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30374612

ABSTRACT

PURPOSE: To evaluate radiofrequency ablation (RFA) for closure of marginal veins in pediatric and adult patients with venous malformations. MATERIALS AND METHODS: Medical records, imaging and procedure details were retrospectively reviewed in patients who underwent RFA of the marginal vein in a 17-month period. Additional sclerotherapy (n = 19) and coil embolization of the marginal vein were performed (n = 2). RESULTS: A total of 23 marginal veins were treated in 20 patients. Mean age at treatment was 16 years ± 9.4 (1-37 years). Pre-procedural magnetic resonance imaging revealed thoracoabdominal marginal veins in 3 patients. A type I marginal vein (draining in the great saphenous vein below the popliteal vein) was identified in 1 and type IIa/IIb (draining in a median/lateral accessory saphenous vein) in 2/8 cases. Type III (draining into the profunda femoral vein) was detected in 8, and type IV (draining into gluteal veins) in 1. Mean diameter of the marginal veins was 13.2 mm ± 4 (7-20 mm). Patency was found in 1 during follow-up (22 months ± 9.8). Complete or partial occlusion was achieved in 94.5% of the veins. One patient showed signs of thrombophlebitis after the procedure, and another incomplete paresis of the peroneal nerve. CONCLUSION: RFA is effective as minimally invasive treatment of the marginal venous system. These veins should be treated early in life. Marginal veins with large diameter, residual tributaries and the intrafascial courses usually require adjunct coil embolization and sclerotherapy. LEVEL OF EVIDENCE: Case series, Level IV.


Subject(s)
Radiofrequency Ablation/methods , Vascular Malformations/therapy , Venous Insufficiency/therapy , Adolescent , Adult , Child , Child, Preschool , Female , Femoral Vein/physiopathology , Follow-Up Studies , Humans , Infant , Male , Retrospective Studies , Saphenous Vein/physiopathology , Treatment Outcome , Vascular Malformations/complications , Vascular Malformations/physiopathology , Vascular Patency/physiology , Venous Insufficiency/physiopathology , Young Adult
6.
Clin Hemorheol Microcirc ; 67(3-4): 355-372, 2017.
Article in English | MEDLINE | ID: mdl-28885203

ABSTRACT

This article presents our experience in managing peripheral vascular malformations of upper and lower extremities over a 4-year period in a series of 46 patients of the Department of Plastic Surgery treated in the Interdisciplinary Center of Vascular Anomalies (ICVA) at the University of Regensburg. The patients presented vascular malformations of upper and lower extremity and were selected from our prospective vascular anomalies file archive from 2012 to 2016. During this period in the ICVA at University of Regensburg were performed more than 1400 radiological interventional treatments in patients with vascular malformations.The purpose of this retrospective study was to review combined embolotherapy, sclerotherapy (embolo/sclerotherapy), and surgical procedures (surgical excision and soft tissue reconstruction) to manage vascular malformations. Treatments were principally induced to reduce pain, daily physical limitations, social discomfort and recover tegument continuity after ulceration.The 46 patients were first examined with noninvasive radiological procedures. After diagnosis was posed, embolo/sclerotherapy, surgical procedures and clinically as well as radiological follow-ups were coordinated and established by the multidisciplinary team. All vascular malformations were categorized according to the classification approved at the April 2014 General Assembly of International Society for the Study of Vascular Anomalies (ISSVA) in Melbourne, Australia. Arteriovenous malformations (AVMs) were further classified following the Cho-Do and Schobinger classification.Embolo/sclerotherapy shows to be the most appropriate procedure in vascular malformations treatment. Nevertheless was found that in case of complications or lack of improvement as well as to improve functional or aesthetical results, a following partial or complete surgical excision and immediate soft tissue reconstruction seems to be the gold-standard treatment. In addition, the precise clinical and radiological diagnosis as well as an intensive postoperative patient care have a significant positive influence on the clinical outcome and patient satisfaction while decreasing morbidity and recurrence during early and late follow-up.Vascular malformations require a multidisciplinary approach and individual treatment after complex excision and indispensable reconstruction.


Subject(s)
Lower Extremity/blood supply , Upper Extremity/blood supply , Vascular Diseases/diagnosis , Vascular Malformations/radiotherapy , Vascular Malformations/surgery , Adolescent , Adult , Aged , Child , Comorbidity , Female , Humans , Male , Middle Aged , Prospective Studies , Retrospective Studies , Treatment Outcome , Young Adult
7.
Arch Orthop Trauma Surg ; 137(10): 1451-1465, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28825132

ABSTRACT

INTRODUCTION: Phalangeal defects are often seen after tumor resection, infections, and in complex open hand fractures. In many cases, reconstruction is difficult and amputation is performed to avoid prolonged rehabilitation that is often associated with a poor outcome. In these cases, the maintenance of length and function presents a reconstructive challenge. METHODS: We reviewed 11 patients who underwent extensive phalangeal reconstruction with non-vascularized bone graft from the iliac crest using a key-in-slot-joint technique to provide acceptable function and bony union. RESULTS: In each case, non-vascularized bone graft with a length of 1.4-6.0 cm was used to reconstruct the phalanx. Follow-up ranged from 6 weeks to 5 months, and in all cases, there was bony union after 6 weeks. We evaluated range of motion, function, and as well pain and grip strength of the fingers. CONCLUSIONS: This case series suggests that a key-in-slot technique allows non-vascularized bone graft to be used in complex large phalangeal bone defects. Due to better bone contact, a sufficient perfusion and revascularisation of the non-vascularized bone graft can be achieved for a quicker and stable bony union. This method appears to be an alternative to amputation in selected cases with a satisfactory soft-tissue envelope.


Subject(s)
Bone Transplantation/methods , Finger Phalanges/surgery , Ilium , Plastic Surgery Procedures/methods , Finger Phalanges/injuries , Humans , Ilium/surgery , Ilium/transplantation , Neovascularization, Physiologic , Retrospective Studies , Treatment Outcome
8.
Clin Hemorheol Microcirc ; 66(4): 347-355, 2017.
Article in English | MEDLINE | ID: mdl-28527203

ABSTRACT

AIM: Comparison of different ultrasound elastography techniques for detection of changes after sclerotherapy within venous malformations. MATERIAL AND METHODS: In patients with venous malformations sonography was executed at exactly the same position prior to and after ethanol-gel sclerotherapy. Both examinations included B-Mode, vascular sonography with Color-Coded Duplex Sonography, and additional sonography with different elastography techniques (strain, qualitative and quantitative Acoustic Radiation Force Impulse (ARFI) elastography) with a linear transducer (6-9 MHz). Qualitative elastograms were read in consensus and scored. Differences of elasticity scores were statistically analyzed, p-values <0.05 were regarded significant. RESULTS: Elasticity scores of strain and qualitative ARFI elastography in 25 patients (21 females, averagely 24.4 years old) were comparable before treatment (p = 0.69). After therapy qualitative ARFI scores changed significantly compared to pre-treatment scores (p = 0.0017), whereas strain elastography scores revealed no significant changes (p = 0.13). Quantitative ARFI values obtained after sclerotherapy within the venous malformations were significantly higher compared to pre-treatment values (p = 0.049), and significantly higher to values obtained in surrounding tissue (p = 0.030). Comparison of pre- and post-treatment ARFI values of the surrounding tissue was not significant (p = 0.67). CONCLUSION: Elasticity scores of qualitative ARFI elastography reliably detect ethanol-gel induced changes in venous malformations. Quantitative ARFI may be a tool for therapy planning, and for monitoring sclerotherapy outcome as well as the effect of sclerosing agents on malformation and surrounding tissue in patients with venous malformations.


Subject(s)
Elasticity Imaging Techniques/methods , Sclerotherapy/methods , Ultrasonography/methods , Vascular Diseases/diagnostic imaging , Adolescent , Adult , Child , Female , Humans , Male , Middle Aged , Vascular Diseases/pathology , Young Adult
9.
Cardiovasc Intervent Radiol ; 39(8): 1099-109, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27307180

ABSTRACT

PURPOSE: To determine the influence of preoperative aneurysmal thrombus quantity and distribution on the development of type II endoleak with aneurysm sac enlargement after endovascular aneurysm repair (EVAR). MATERIALS AND METHODS: We retrospectively analyzed the pre- and postoperatively performed CT scans of 118 patients who had follow-up imaging for at least 1 year after EVAR available. We assessed preoperative thrombus perimeter (T Peri), diameter (T Dia), cross-sectional area (T CSA), and volume (T Vol). The preoperative thrombus distribution was classified into no thrombus, semilunar-shaped (anterior, right side, left side, posterior) thrombus, and circumferential type thrombus. The number of preoperative patent aortic side branches (ASB) was identified. Endpoint was type II endoleak with aneurysm volume (A Vol) increase of ≥5 % during follow-up. RESULTS: During follow-up (2 years, range 1-9 years), 17 patients with type II endoleak had significant A Vol increase. Less preoperative T Peri, T Dia, T CSA, and T Vol were associated with A Vol increase. A circumferential thrombus distribution significantly protected against aneurysm enlargement (p = 0.028). The variables with the strongest significance for A Vol increase were preoperative T Vol/A Vol ratio (OR 0.95; p = 0.037) and number of patent ASB (OR 3.52; p < 0.001). CONCLUSION: A low preoperative T Vol/A Vol ratio and a high number of patent ASB were associated with aneurysm sac enlargement after EVAR.


Subject(s)
Aortic Aneurysm, Abdominal/diagnostic imaging , Aortic Aneurysm, Abdominal/surgery , Endoleak/epidemiology , Endovascular Procedures/methods , Postoperative Complications/epidemiology , Preoperative Period , Aged , Aged, 80 and over , Endoleak/diagnostic imaging , Female , Follow-Up Studies , Humans , Male , Middle Aged , Retrospective Studies , Risk Factors , Stents , Tomography, X-Ray Computed , Treatment Outcome
12.
Eur J Radiol ; 84(10): 1964-9, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26137903

ABSTRACT

PURPOSE: To evaluate the technical and clinical success of percutaneous superior mesenteric vein (SMV) stenting in symptomatic patients using self-expanding nitinol stents. METHODS: We retrospectively analyzed the technical and clinical success of percutaneous SMV stenting of 6 symptomatic patients (3 men, mean age 67 years, range 48-81 years). Stenosis of the SMV was caused by postoperative stricture (n=3), pancreas carcinoma (n=1) and pancreatitis (n=2). As a result of the stenosis, 3 patients had symptomatic ascites, 2 patients showed signs of mesenteric ischemia and 1 patient had recurrent gastrointestinal bleeding. Stenting was performed by a percutaneous transhepatic approach using self-expanding nitinol stents. RESULTS: Stenting of the SMV was technically and clinically successful in all patients. No peri-interventional complications occurred. The stent diameters ranged from 6 to 14 mm. During the mean follow-up of 6 months (range, 2-10 months) 1 patient presented early stent occlusion 2 weeks after placement. CONCLUSION: Stenting of a symptomatic SMV stenosis using self-expanding nitinol stents is feasible and clinically effective.


Subject(s)
Mesenteric Vascular Occlusion/surgery , Mesenteric Veins/surgery , Self Expandable Metallic Stents , Aged , Aged, 80 and over , Alloys/chemistry , Anticoagulants/therapeutic use , Ascites/etiology , Catheterization/instrumentation , Constriction, Pathologic/surgery , Female , Follow-Up Studies , Heparin, Low-Molecular-Weight/therapeutic use , Humans , Male , Mesenteric Ischemia/etiology , Mesenteric Vascular Occlusion/etiology , Mesenteric Veins/diagnostic imaging , Middle Aged , Pancreatic Neoplasms/complications , Pancreatitis/complications , Portal Vein/surgery , Postoperative Complications , Punctures/instrumentation , Retrospective Studies , Treatment Outcome , Ultrasonography, Doppler, Color
14.
Eur Radiol ; 24(10): 2449-57, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24965507

ABSTRACT

OBJECTIVES: To assess the diagnostic accuracy of dual-energy computed tomography (DECT) for detection of endoleaks and aneurysm sac calcifications after endovascular aneurysm repair (EVAR) using hard plaque imaging algorithms. MATERIALS AND METHODS: One hundred five patients received 108 triple-phase contrast-enhanced CT (non-contrast, arterial and delayed phase) after EVAR. The delayed phase was acquired in dual-energy and post-processed using the standard (HPI-S) and a modified (HPI-M) hard plaque imaging algorithm. The reference standard was determined using the triple-phase CT and contrast-enhanced ultrasound. All images were analysed separately for the presence of endoleaks and calcifications by two independent readers; sensitivity, specificity and interobserver agreement were calculated. RESULTS: Endoleaks and calcifications were present in 25.9 % (28/108) and 20.4 % (22/108) of images. The HPI-S images had a sensitivity/specificity of 54 %/100 % (reader 1) and 57 %/99 % (reader 2), the HPI-M images of 93 %/92 % (reader 1) and 96 %/92 % (reader 2) for detection of endoleaks. For detection of calcifications HPI-S had a sensitivity/specificity of 91 %/99 % (reader 1) and 95 %/97 % (reader 2), the HPI-M images of 91 %/99 % (reader 1) and 91 %/99 % (reader 2), respectively. CONCLUSION: Using HPI-M, DECT enables an accurate diagnosis of endoleaks after EVAR and allows distinguishing between endoleaks and calcifications with high diagnostic accuracy. KEY POINTS: • Dual-energy computed tomography allows the diagnosis of aortic pathologies after EVAR. • Hard plaque imaging algorithms can distinguish between endoleaks and aneurysm sac calcifications. • The modified hard plaque imaging algorithm detects endoleaks with high diagnostic accuracy.


Subject(s)
Aortic Aneurysm, Abdominal/diagnostic imaging , Calcinosis/complications , Endoleak/diagnostic imaging , Endovascular Procedures/methods , Image Processing, Computer-Assisted/methods , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Algorithms , Aortic Aneurysm, Abdominal/complications , Aortic Aneurysm, Abdominal/surgery , Calcinosis/diagnostic imaging , Endoleak/etiology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , ROC Curve , Reproducibility of Results
16.
Rofo ; 186(7): 693-7, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24458376

ABSTRACT

PURPOSE: Evaluation of the efficacy and safety of Gelfoam for the closure of transhepatic or transsplenic parenchymal puncture tracts with large-bore sheaths in pediatric patients. MATERIALS AND METHODS: Between January 2012 and May 2013, 8 percutaneous transhepatic accesses and 3 percutaneous transsplenic accesses were closed using percutaneous Gelfoam in pediatric patients. The primary study endpoints to determine treatment efficacy and safety were patient survival, technical success defined as successful closure of the puncture tract without signs of bleeding, and complication rates. The secondary study endpoints were the occurrence of local and systemic inflammation. RESULTS: Overall survival was 100 % with a median follow-up of 256 days. The procedure was technically successful in 10 of 11 procedures. One patient suffered from bleeding, which was successfully managed by a single blood transfusion. No re-bleeding was detected during follow-up and no surgical interventions were necessary. No signs of local or systemic infections related to the Gelfoam application occurred. CONCLUSION: Percutaneous Gelfoam application is an effective and safe technique for the closure of transhepatic or transsplenic accesses in pediatric patients. KEY POINTS: Interventional closure of large transhepatic and transsplenic parenchymal accesses in children after interventional treatment is recommended to avoid bleeding. Gelfoam application does not cause artifacts in magnetic resonance imaging and does not increase the risk of local or systemic inflammation in comparison to permanent embolic agents. Thus, especially children under immunosuppressive therapy can benefit from the application of Gelfoam.


Subject(s)
Embolization, Therapeutic/methods , Gelatin Sponge, Absorbable/therapeutic use , Hemorrhage/etiology , Hemorrhage/therapy , Hemostatics/therapeutic use , Punctures/adverse effects , Wound Closure Techniques , Child , Child, Preschool , Female , Humans , Infant , Male , Portal Vein/surgery , Retrospective Studies , Treatment Outcome
17.
Rofo ; 186(2): 142-50, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24127345

ABSTRACT

PURPOSE: To report on first results of the embolization of transhepatic and transsplenic puncture tracts using an Amplatzer Vascular Plug (AVP) after percutaneous portal vein intervention. MATERIALS AND METHODS: Embolization of transhepatic and transsplenic puncture tracts with AVP was attempted in 5 patients (3 females; age range: 3 - 71 years). Portal vein access was gained by a transhepatic (n = 4) or transsplenic (n = 1) approach, and stenosis (n = 2) or thrombosis (n = 3) of the portal vein was successfully treated by percutaneous stenting or thrombus aspiration and thrombolysis using 6 to 10 French sheaths. Due to the relatively large bore and/or short transparenchymal puncture tracts, it was considered favorable to use AVPs as an embolic agent. The medical records, the radiological reports and images of these 5 patients were retrospectively evaluated. RESULT: In three cases one AVP II (diameter, 4 mm), in one case one AVP IV (diameter, 4 mm) and in one case two AVPs II (diameter, 8 and 6 mm) were used for embolization of the puncture tract. In all five cases embolization was technically successful. There was no bleeding from the puncture tract. During a median follow-up of 14 months (range, 21 days to 21 months), one patient developed a focal liver abscess adjacent to the AVP which was successfully treated by antimicrobial and drainage therapy. There were no further embolization-related complications. CONCLUSION: AVPs are suited to embolize large bore and/or short transhepatic and transsplenic puncture tracts effectively, safely, and precisely. Caution is required in patients with an increased risk for infectious complications. KEY POINTS: • Embolization of transhepatic and transsplenic puncture tracts with AVPs is feasible• Large and/or short puncture tracts can be effectively embolized with AVPs• The risk of infectious complications has to be considered Citation Format: • Dollinger M, Goessmann H, Mueller-Wille R et al. Percutaneous Transhepatic and Transsplenic Portal Vein Access: Embolization of the Puncture Tract Using Amplatzer Vascular Plugs. Fortschr Röntgenstr 2014; 186: 142 - 150.


Subject(s)
Catheterization, Peripheral/instrumentation , Hemorrhage/etiology , Hemorrhage/prevention & control , Portal Vein/injuries , Punctures/adverse effects , Septal Occluder Device , Splenic Vein/injuries , Adolescent , Adult , Catheterization, Peripheral/methods , Child , Child, Preschool , Embolization, Therapeutic , Female , Hemorrhage/diagnostic imaging , Humans , Male , Middle Aged , Portal Vein/diagnostic imaging , Radiography , Splenic Vein/diagnostic imaging , Treatment Outcome , Young Adult
18.
Rofo ; 184(10): 992-7, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23893750

ABSTRACT

PURPOSE: To evaluate the extent to which MRE can be used as an observer-independent, objective imaging method for the diagnosis and evaluation of CD with respect to the detection of inflammatory changes of the small bowel and lymphadenopathy as diagnostic criterion and bowel distension as a quality criterion. MATERIALS AND METHODS: MRE scans of 84 patients (42 female, median age 37 years) were evaluated independently by 4 experienced radiologists. Analysis of inflammatory changes of the bowel wall, lymphadenopathy and adequate bowel distension was conducted separately for the jejunum, ileum and terminal ileum. The Kendall's W-test was used for the statistical comparison of concordance. RESULTS: In a total of 55 patients, inflammatory activity of the bowel wall was detected and MRE was found to have a high interobserver reproducibility concerning inflammatory changes of the intestinal wall (Kendall's W 0.527 - 0.823). Concerning lymphadenopathy (31 cases, 36.9 %), a low to moderate consensus could be shown with a Kendall's W value of 0.402 - 0.505. For the assessment of adequate bowel distension, a moderate concordance between the operators could be found (Kendall's W 0.497 - 0.581). CONCLUSION: MRE has proven high interobserver agreement with respect to the diagnosis of inflammatory disease activity of the bowel as a diagnostic criterion in patients with CD. Concerning adequate bowel distension as a quality criterion of the examination itself and lymphadenopathy as a diagnostic criterion, moderate interobserver agreement could be found. This is thought to have a rather small effect on the diagnostic significance and conclusiveness of the method in the daily routine. KEY POINTS: ▶ MR enterography as observer independent diagnostic procedure in patients with Chron's Disease. ▶ Highest interobserver concordance for the criterion of inflammatory bowel wall affection. ▶ Moderate interobserver concordance for lymphadenopathy and bowel distension.


Subject(s)
Crohn Disease/diagnosis , Ileum/pathology , Image Interpretation, Computer-Assisted/methods , Jejunum/pathology , Magnetic Resonance Imaging/methods , Adult , Contrast Media , Diagnosis, Differential , Female , Follow-Up Studies , Gadolinium DTPA , Humans , Lymph Nodes/pathology , Lymphatic Diseases/diagnosis , Male , Observer Variation , Prospective Studies , Sensitivity and Specificity
19.
Rofo ; 185(12): 1182-7, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23860801

ABSTRACT

PURPOSE: The management of postoperative bile leakage is challenging especially if the leak rises from the cut surface of the liver and endoscopic treatment fails. Percutaneous transhepatic treatment of bile leaks with biliary drainage is accepted but often requires long-term placement of the drains and is associated with treatment failures. This series evaluates selective embolization of bile ducts with an ethylene vinyl alcohol copolymer (Onyx) in patients with postoperative bile leaks as an alternative treatment option. MATERIALS AND METHODS: Between January and September 2012, five consecutive patients with persistent postoperative bile leaks underwent percutaneous transhepatic Onyx application and were analyzed regarding procedural management, complications and success rates. RESULTS: The persistent bile leaks were situated at the cystic stump (after cholecystectomy, n = 2), at the cut surface of the liver (after extended liver resection, n = 2) and at the surface of the liver after surgical exploration and perihepatic abscess (n = 1). Bile drainage alone (endoscopic or percutaneous) failed in all patients and open redo-surgery was deemed potentially harmful. Bilomas were externally drained in all patients before Onyx application. For the closure of bile leaks, Onyx was injected through a microcatheter in a previously built coil nest to keep Onyx in place. All bile leaks were initially closed immediately. In the 2nd week after Onyx embolization, 2 patients showed recurrent small bile leaks without clinical symptoms. In the 4th week after Onyx application, all leaks were closed. No complications occurred. CONCLUSION: All leaking bile ducts were initially closed immediately after Onyx application. In the 2nd week after Onyx application, 2 patients showed small bile leaks without clinical symptoms. All leaks were closed in the 4th week after Onyx application.


Subject(s)
Biliary Fistula/therapy , Dimethyl Sulfoxide/administration & dosage , Embolization, Therapeutic/methods , Polyvinyls/administration & dosage , Postoperative Complications/therapy , Aged , Anastomotic Leak/diagnosis , Anastomotic Leak/therapy , Biliary Fistula/diagnosis , Cholangiography/instrumentation , Cholangiography/methods , Drainage/methods , Embolization, Therapeutic/instrumentation , Female , Humans , Male , Middle Aged , Postoperative Complications/diagnosis , Radiology, Interventional/methods , Tomography, X-Ray Computed
20.
Eur J Radiol ; 82(10): 1710-5, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23806531

ABSTRACT

PURPOSE: The purpose of this study was to assess differences in enhancement effects of liver parenchyma between normal and cirrhotic livers on dynamic, Gd-EOB-DTPA enhanced MRI at 3T. MATERIALS AND METHODS: 93 patients with normal (n=54) and cirrhotic liver (n=39; Child-Pugh class A, n=18; B, n=16; C, n=5) underwent contrast-enhanced MRI with liver specific contrast media at 3T. T1-weighted volume interpolated breath hold examination (VIBE) sequences with fat suppression were acquired before contrast injection, in the arterial phase (AP), in the late arterial phase (LAP), in the portal venous phase (PVP), and in the hepatobiliary phase (HBP) after 20 min. The relative enhancement (RE) of the signal intensity of the liver parenchyma was calculated for all phases. RESULTS: Mean RE was significantly different among all evaluated groups in the hepatobiliary phase and with increasing severity of liver cirrhosis, a decreasing, but still significant reduction of RE could be shown. Phase depending changes of RE for each group were observed. In case of non-cirrhotic liver or Child-Pugh Score A cirrhosis mean RE showed a significant increase between AP, LAP, PVP and HBP. For Child-Pugh B+C cirrhosis RE increased until PVP, however, there was no change in case of B cirrhosis (p=0.501) and significantly reduced in case of C cirrhosis (p=0.043) during HBP. CONCLUSION: RE of liver parenchyma is negatively affected by increased severity of liver cirrhosis, therefore diagnostic value of HBP could be limited in case of Child Pugh B+C cirrhosis.


Subject(s)
Algorithms , Gadolinium DTPA , Image Enhancement/methods , Liver Cirrhosis/pathology , Liver/pathology , Magnetic Resonance Imaging/methods , Contrast Media , Female , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity
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