Where Have All the Punctures Gone? An Analysis of Thoracic Duct Embolizations.

PURPOSE: To determine how frequently and how severely intra-abdominal structures are affected by transabdominal thoracic duct embolization (TDE). MATERIALS AND METHODS: Thirty-five TDE procedures in 35 patients (22 male; mean age, 57 y; age range, 10-79 y) with therapy-refractory chylous effusions were evaluated in which radiopaque embolization material outlined the access route on postinterventional CT. CT data were analyzed by 2 TDE-experienced radiologists. Abdominal structures and organs transgressed by the access route were recorded, and findings were correlated with clinical postinterventional course with follow-up of at least 44 days. RESULTS: Intra-abdominal structures/organs transgressed most often by the access route were the liver (n = 28), crus of the diaphragm (n = 25), pancreas (n = 14), portal vein (n = 10), duodenum (n = 7), inferior vena cava (n = 5), colon (n = 3), left renal vein (n = 2), pleura (n = 2), pericardium (n = 2), and gastric sleeve (n = 2). Pancreatitis was observed in 1 of 14 patients after pancreatic transgression. One case of clinically occult pulmonary glue migration occurred on catheter pullback through the left renal vein. Biliary peritonitis was observed after gallbladder puncture, necessitating cholecystectomy in 1 of 2 transbiliary punctures. No other relevant procedure-related complications such as hemorrhages or infectious complications were observed. CONCLUSIONS: Despite transgression of intra-abdominal structures, puncture- and access-related complications of TDE are rare. Transpancreatic manipulations are reasonably well tolerated.

Tomotherapy in malignant mesothelioma: a planning study to establish dose constraints.

PURPOSE: A planning study was performed for helical tomotherapy treatment. We evaluated the maximum achievable protection of organs at risk (OARs) in patients with malignant pleural mesothelioma after pleurectomy with simultaneous optimal target coverage. MATERIALS AND METHODS: The datasets of 13 patients were included. The applied dose to the planning target volume (PTV) was 50.4 Gy with single doses of 1.8 Gy per fraction. Presuming optimal target coverage, we evaluated the applied dose to the OARs with special regard to the contralateral lung. RESULTS: For left-(lsRT)/right(rsRT)-sided radiotherapy, target coverage for the PTV showed a D98 (mean) of 49.37/49.71 Gy (98.0%/98.6%) and a D2 (mean) of 54.19/54.61 Gy (107.5%/108.3%). The beam-on time was kept below 15 min. The achieved mean dose (D50) to the contralateral lung was kept below 4 Gy for lsRT and rsRT. With regard to the other organs at risk the applied doses were as follows: mean dose (lsRT): ipsilateral kidney (Dmean) 13.03 (5.32-22.18) Gy, contralateral kidney (Dmean) <2.0 Gy, heart (Dmean) 22.23 (13.57-27.72) Gy, spinal cord D1

Lung cancer screening with MRI: Evaluation of MRI for lung cancer screening by comparison of LDCT- and MRI-derived Lung-RADS categories in the first two screening rounds.

PURPOSE: To evaluate MRI for lung cancer screening comparing LDCT- and MRI-derived Lung-RADS categories in the first two screening rounds. MATERIALS AND METHODS: 224 participants in a lung cancer screening study were examined with MRI and low-dose CT (LDCT). Acquired MRI sequences were T2, balanced, T1 and DWI. MRI was prospectively analysed regarding nodules. Minimum nodule size was 4 mm. Nodules were assigned a Lung-RADS score based on appearance and size at baseline and after 3, 6 and 12 months. MRI findings were correlated with LDCT. RESULTS: The early recall rate dropped from 13.8% at baseline to 1.9% in the second screening round with biopsy rates of 3.6% in the first round and 0.5% in the second round. Histology revealed lung cancer in 8/9 participants undergoing biopsy/surgery. All eight cancers were accurately depicted by MRI. The following categories were assigned on MRI (results of LDCT in parentheses): 4B/4X in 10 (10) cases, 4A in 16 (15) cases, 3 in 13 (12) cases, 2 in 77 (92) cases and 1 in 140 (126) cases. Lung-RADS scoring correlated significantly between MRI and CT. The score was overestimated by MRI in one case for category 4A, in two cases for category 3 and in five cases for category 2. MRI-based Lung-RADS score was underestimated for category 1 in 20 cases. CONCLUSION: Lung-RADS might be applied for lung cancer screening with MRI, since findings correlated with LDCT. Relevant findings with a Lung-RADS score of 3 and higher were never missed or underestimated by MRI KEY POINTS: • MRI performed comparably to low-dose CT in a lung cancer-screening programme. • Lung-RADS might be applied for lung cancer screening with MRI. • Lung-RADS findings score of 3 and higher were never missed by MRI.

Lung cancer screening with MRI: characterization of nodules with different non-enhanced MRI sequences.

BACKGROUND: There is increased interest in pulmonary magnetic resonance imaging (MRI) as a radiation-free alternative to computed tomography (CT) for lung cancer screening. PURPOSE: To analyze MRI characteristics of pulmonary nodules with different non-enhanced sequences. MATERIAL AND METHODS: Eighty-two participants of a lung cancer screening were included. MRI datasets of 32 individuals with 46 different nodules ≥ 6 mm were prospectively evaluated together with 50 controls by two readers. Acquired sequences were T2- short tau inversion recovery (STIR), T2, balanced steady-state free precession (bSSFP), 3D-T1, and diffusion-weighted imaging (DWI). Each sequence was randomly and separately viewed blinded to low-dose CT (LDCT). Size, shape, and contrast of nodules were evaluated on each sequence and then correlated with LDCT and histopathology. RESULTS: All eight carcinomas were detected by T2-STIR, T2, and bSSFP, and 7/8 by 3D-T1. Contrast was significantly higher for malignant nodules on all sequences. The highest contrast ratio between malignant and benign nodules was provided by T2-STIR. Of eight carcinomas, seven showed restricted diffusion. Size measurement correlated significantly between MRI and LDCT. Sensitivity/specificity for nodules ≥ 6 mm was 85-89%/92-94% for T2-STIR, 80-87%/93-96% for T2, 65-70%/96-98% for bSSFP, and 63-67%/96-100% for 3D-T1. Seven of eight subsolid nodules were visible on T2-sequences with significantly lower lesion contrast compared to solid nodules. Two of eight subsolid nodules were detected by bSFFP, none by 3D-T1. All three calcified nodules were detected by 3D-T1, one by bSSFP, and none by T2-sequences. CONCLUSION: Malignant as well as calcified and subsolid nodules seem to have distinctive characteristics on different MRI sequences. T2-imaging was most suitable for the detection of nodules ≥ 6 mm.

[Chylothorax: Current Therapeutic Options]. / Chylothorax: eine Übersicht über aktuelle therapeutische Möglichkeiten.

Therapeutic options in management of chylothorax encompass conservative, surgical and also interventional measures. Despite the fact that interventions have been performed in substantial numbers of patients - particularly thoracic duct embolisations - general knowledge about this therapeutic option is still limited. Therefore, this article gives an overview of the state of the art for therapeutic options, also emphasising radiological/interventional procedures. At present, interventional treatment has lower morbidity and mortality, and is especially indicated after failed surgical therapy, or in inoperable patients.

Patient positioning in head and neck cancer : Setup variations and safety margins in helical tomotherapy.

OBJECTIVE: To evaluate the interfractional variations of patient positioning during intensity-modulated radiotherapy (IMRT) with helical tomotherapy in head and neck cancer and to calculate the required safety margins (sm) for bony landmarks resulting from the necessary table adjustments. MATERIALS AND METHODS: In all, 15 patients with head and neck cancer were irradiated using the Hi-Art II tomotherapy system between April and September 2016. Before therapy sessions, patient position was frequently checked by megavolt computed tomography (MV-CT). Necessary table adjustments (ta) in the right-left (rl), superior-inferior (si) and anterior-posterior (ap) directions were recorded for four anatomical points: second, fourth and sixth cervical vertebral body (CVB), anterior nasal spine (ANS). Based upon these data sm were calculated for non-image-guided radiotherapy, image-guided radiotherapy (IGRT) and image guidance limited to a shortened area (CVB 2). RESULTS: Based upon planning CT the actual treatment required ta from -0.05 ± 1.31 mm for CVB 2 (ap) up to 2.63 ± 2.39 mm for ANS (rl). Considering the performed ta resulting from image control (MV-CT) we detected remaining ta from -0.10 ± 1.09 mm for CVB 4 (rl) up to 1.97 ± 1.64 mm for ANS (si). After theoretical adjustment of patients position to CVB 2 the resulting ta ranged from -0.11 ± 2.44 mm for CVB6 (ap) to 2.37 ± 2.17 mm for ANS (si). These data imply safety margins: uncorrected patient position: 3.63-9.95 mm, corrected positioning based upon the whole target volume (IGRT): 1.85-6.63 mm, corrected positioning based upon CVB 2 (IGRT): 3.13-6.66 mm. CONCLUSIONS: The calculated safety margins differ between anatomic regions. Repetitive and frequent image control of patient positioning is necessary that, however, possibly may be focussed on a limited region.

Revised PROPELLER for T2-weighted imaging of the prostate at 3 Tesla: impact on lesion detection and PI-RADS classification.

PURPOSE: To evaluate revised PROPELLER (RevPROP) for T2-weighted imaging (T2WI) of the prostate as a substitute for turbo spin echo (TSE). MATERIALS AND METHODS: Three-Tesla MR images of 50 patients with 55 cancer-suspicious lesions were prospectively evaluated. Findings were correlated with histopathology after MRI-guided biopsy. T2 RevPROP, T2 TSE, diffusion-weighted imaging, dynamic contrast enhancement, and MR-spectroscopy were acquired. RevPROP was compared to TSE concerning PI-RADS scores, lesion size, lesion signal-intensity, lesion contrast, artefacts, and image quality. RESULTS: There were 41 carcinomas in 55 cancer-suspicious lesions. RevPROP detected 41 of 41 carcinomas (100%) and 54 of 55 lesions (98.2%). TSE detected 39 of 41 carcinomas (95.1%) and 51 of 55 lesions (92.7%). RevPROP showed fewer artefacts and higher image quality (each p < 0.001). No differences were observed between single and overall PI-RADS scores based on RevPROP or TSE (p = 0.106 and p = 0.107). Lesion size was not different (p = 0.105). T2-signal intensity of lesions was higher and T2-contrast of lesions was lower on RevPROP (each p < 0.001). CONCLUSION: For prostate cancer detection RevPROP is superior to TSE with respect to motion robustness, image quality and detection rates of lesions. Therefore, RevPROP might be used as a substitute for T2WI. KEY POINTS: • Revised PROPELLER can be used as a substitute for T2-weighted prostate imaging. • Revised PROPELLER detected more carcinomas and more suspicious lesions than TSE. • Revised PROPELLER showed fewer artefacts and better image quality compared to TSE. • There were no significant differences in PI-RADS scores between revised PROPELLER and TSE. • The lower T2-contrast of revised PROPELLER did not impair its diagnostic quality.

Proton density fat fraction (PDFF) MR imaging for differentiation of acute benign and neoplastic compression fractures of the spine.

OBJECTIVES: To evaluate the diagnostic performance of proton density fat fraction (PDFF) magnetic resonance imaging (MRI) to differentiate between acute benign and neoplastic vertebral compression fractures (VCFs). METHODS: Fifty-seven consecutive patients with 46 acute benign and 41 malignant VCFs were prospectively enrolled in this institutional review board approved study and underwent routine clinical MRI with an additional six-echo modified Dixon sequence of the spine at a clinical 3.0-T scanner. All fractures were categorised as benign or malignant according to either direct bone biopsy or 6-month follow-up MRI. Intravertebral PDFF and PDFFratio (fracture PDFF/normal vertebrae PDFF) for benign and malignant VCFs were calculated using region-of-interest analysis and compared between both groups. Additional receiver operating characteristic and binary logistic regression analyses were performed. RESULTS: Both PDFF and PDFFratio of malignant VCFs were significantly lower compared to acute benign VCFs [PDFF, 3.48 ± 3.30% vs 23.99 ± 11.86% (p < 0.001); PDFFratio, 0.09 ± 0.09 vs 0.49 ± 0.24 (p < 0.001)]. The areas under the curve were 0.98 for PDFF and 0.97 for PDFFratio, yielding an accuracy of 96% and 95% for differentiating between acute benign and malignant VCFs. PDFF remained as the only imaging-based variable to independently differentiate between acute benign and malignant VCFs on multivariate analysis (odds ratio, 0.454; p = 0.005). CONCLUSIONS: Quantitative assessment of PDFF derived from modified Dixon water-fat MRI has high diagnostic accuracy for the differentiation of acute benign and malignant vertebral compression fractures. KEY POINTS: • Chemical-shift-encoding based water-fat MRI can reliably assess vertebral bone marrow PDFF • PDFF is significantly higher in acute benign than in malignant VCFs • PDFF provides high accuracy for differentiating acute benign from malignant VCFs.

Proton density fat fraction (PDFF) MRI for differentiation of benign and malignant vertebral lesions.

OBJECTIVES: To investigate whether proton density fat fraction (PDFF) measurements using a six-echo modified Dixon sequence can help to differentiate between benign and malignant vertebral bone marrow lesions. METHODS: Sixty-six patients were prospectively enrolled in our study. In addition to conventional MRI at 3.0-Tesla including at least sagittal T2-weighted/spectral attenuated inversion recovery and T1-weighted sequences, all patients underwent a sagittal six-echo modified Dixon sequence of the spine. The mean PDFF was calculated using regions of interest and compared between vertebral lesions. A cut-off value of 6.40% in PDFF was determined by receiver operating characteristic curves and used to differentiate between malignant (< 6.40%) and benign (≥ 6.40%) vertebral lesions. RESULTS: There were 77 benign and 44 malignant lesions. The PDFF of malignant lesions was statistically significant lower in comparison with benign lesions (p < 0.001) and normal vertebral bone marrow (p < 0.001). The areas under the curves (AUC) were 0.97 for differentiating benign from malignant lesions (p < 0.001) and 0.95 for differentiating acute vertebral fractures from malignant lesions (p < 0.001). This yielded a diagnostic accuracy of 96% in the differentiation of both benign lesions and acute vertebral fractures from malignancy. CONCLUSION: PDFF derived from six-echo modified Dixon allows for differentiation between benign and malignant vertebral lesions with a high diagnostic accuracy. KEY POINTS: • Establishing a diagnosis of indeterminate vertebral lesions is a common clinical problem • Benign bone marrow processes may mimic the signal alterations observed in malignancy • PDFF differentiates between benign and malignant lesions with a high diagnostic accuracy • PDFF of non-neoplastic vertebral lesions is significantly higher than that of malignancy • PDFF from six-echo modified Dixon may help avoid potentially harmful bone biopsy.

Prophylactically applied Hydrofilm polyurethane film dressings reduce radiation dermatitis in adjuvant radiation therapy of breast cancer patients.

PURPOSE: Radiation-induced skin injury represents one of the most common side effects in breast cancer patients receiving adjuvant whole-breast radiotherapy. Numerous systemic and topical treatments have been studied in the prevention and management of radiation-induced skin injury without providing sustainable treatment strategies. While superficial barrier-forming skin products such as dressings are the standard of care in wound care management, their utilization as preventive treatment approach in radiotherapy has barely attracted attention. METHODS: In this prospective, intra-patient randomized study, Hydrofilm polyurethane film dressings were applied prophylactically to either the medial or lateral breast half of 62 patients with breast cancer undergoing adjuvant radiation therapy following breast conserving surgery. The breast half contralateral to the film dressing was concurrently treated with 5% urea lotion as control skin care. Maximum severity of radiation dermatitis was assessed using RTOG/EORTC toxicity scores, photospectrometric erythema measurements and patient-assessed modified RISRAS scale. RESULTS: In the Hydrofilm compartments, mean maximum RTOG/EORTC radiation dermatitis severity grades were significantly reduced from 1.33 to 0.35 and photospectrometric measurements showed significantly reduced erythema severity, as compared to the control compartments, with an overall response rate of 89.3%. Hydrofilm completely prevented moist desquamation and significantly reduced patients' subjective experience of itching and pain. CONCLUSION: The obtained results along with a favorable cost-benefit ratio and an easy and quick application suggest a prophylactic application of Hydrofilm in adjuvant radiotherapy of breast cancer patients to reduce or even prevent radiation dermatitis.

Diffusion-weighted magnetic resonance imaging predicts survival in patients with liver-predominant metastatic colorectal cancer shortly after selective internal radiation therapy.

OBJECTIVES: To investigate whether quantifications of apparent diffusion coefficient (ADC) on diffusion-weighted imaging (DWI) can predict overall survival (OS) in patients with liver-predominant metastatic colorectal cancer (CRC) following selective internal radiation therapy with 90Yttrium-microspheres (SIRT). METHODS: Forty-four patients underwent DWI 19 ± 16 days before and 36 ± 10 days after SIRT. Tumour-size and intratumoral minimal ADC (minADC) values were measured for 132 liver metastases on baseline and follow-up DWI. Optimal functional imaging response to treatment was determined by receiver operating characteristics and defined as ≥22 % increase in post-therapeutic minADC. Survival analysis was performed with the Kaplan-Meier method and Cox-regression comparing various variables with potential impact on OS. RESULTS: Median OS was 8 months. The following parameters were significantly associated with median OS: optimal functional imaging response (18 vs. 5 months; p < 0.001), hepatic tumour burden <50 % (8 vs. 5 months; p = 0.018), Eastern Cooperative Oncology Group performance scale <1 (10 vs. 4 months; p = 0.012) and progressive disease according to Response and Evaluation Criteria in Solid Tumours (8 vs. 3 months; p = 0.001). On multivariate analysis, optimal functional imaging response and hepatic tumour burden remained independent predictors of OS. CONCLUSION: Functional imaging response assessment using minADC changes on DWI may predict survival in CRC shortly after SIRT. KEY POINTS: • Relative minADC changes may predict survival in liver-predominant metastatic colorectal cancer following SIRT • Intratumoral minADC changes by ≥22 % were best to predict an improved overall survival • Functional imaging response assessment is feasible before anatomic tumour-size changes occur • minADC changes might guide future therapy management in sequential lobar radioembolization approaches.

Prospective Evaluation of Passive Expansion of Partially Dilated Transjugular Intrahepatic Portosystemic Shunt Stent Grafts-A Three-Dimensional Sonography Study.

PURPOSE: To prospectively investigate early expansion kinetics of underdilated self-expanding stent grafts used for transjugular intrahepatic portosystemic shunt (TIPS) creation. MATERIALS AND METHODS: Twenty patients (7 female; mean age 66 y; range, 31-80 y) with liver cirrhosis undergoing TIPS creation for variceal bleeding (n = 5), refractory ascites (n = 14), or both (n = 1) with underdilation of 10-mm stent grafts received two-dimensional (2-D) and three-dimensional (3-D) ultrasound (US) examinations immediately after TIPS creation and 1 and 6 weeks later. Orthogonal views of the TIPS within the parenchymal tract were reconstructed from 3-D volume data sets acquired in longitudinal orientation of the stent. 2-D images and reconstructed 3-D images were used for blinded diameter measurements. Measurement technique was validated with intrainterventional plain radiographs with a sizing catheter as the gold standard. Diameter changes over time and interrelations with patient characteristics (null hypothesis: no expansion, no interrelation) were analyzed using a general linear model for repeated measures. RESULTS: After dilation to 8-mm diameter, 2-D and 3-D measurements showed stent recoil (mean diameter 7.7 mm ± 0.21 and 7.6 mm ± 0.17, respectively). Diameter increased significantly from initial measurements to measurements at 1 and 6 weeks (2-D, 8.8 mm ± 0.24 and 9.4 mm ± 0.15, both P < .001; 3-D, 8.7 mm ± 0.27 and 9.4 mm ± 0.11, both P < .001). Validation measurements showed no significant differences between 2-D or 3-D US and gold standard. There were no statistically significant associations between stent expansion and clinical parameters (sex, P = .78; age, P = .82; etiology/grade of cirrhosis, P = .99; indication for TIPS, P = .78, liver stiffness, P = .70). CONCLUSIONS: Underdilated self-expanding stent grafts used for TIPS creation significantly expand within first 6 weeks after intervention. These changes can be noninvasively monitored using 3-D US.

Classification of spondylolytic clefts in patients with spondylolysis or isthmic spondylolisthesis using positional MRI.

Background Posterior instability is a pathologic movement occurring in the spondylolytic cleft. Purpose To present a new classification system for the evaluation of spondylolytic cleft by positional magnetic resonance imaging (MRI) and determine the prevalence of the different types. Material and Methods A total of 176 segments of the lumbar spine with spondylolysis or isthmic spondylolisthesis were examined using positional MRI. Scans were obtained in neutral sitting, flexion, and extension positions. No visible movement in the cleft was defined as type A, fluid displaced into the cleft as type BI, displacement of the flava ligaments at the level of the cleft as type BII, and intraspinal cysts arising from the spondylolytic cleft as type BIII. The movements were characterized by a radiologist and a neurosurgeon experienced in positional MRI. Clinical findings were correlated with the different types of instability. Results A high agreement was found between the two observers. In total, 131 segments were characterized as type A, six as type BI, 24 as type BII, and 10 as type BIII. In five segments, the type differed between the right and the left side. Two patients had a mixed type BI/II, another two patients had a mixed type BII/III, and one patient had a mixed type BI/III. Patients with type BII and BIII instabilities suffered more often from radicular symptoms compared to patients without any instability. Conclusion The presented classification might help to better understand and study changes encountered in the spondylolytic cleft in patients with spondylolysis and isthmic spondylolisthesis using positional MRI.

[Interventional Radiological Treatment of Intercostal Artery Bleedings - a Retrospective Analysis]. / Interventionell-radiologische Behandlung von Interkostalarterienblutungen ­ eine retrospektive Analyse.

Background Intercostal artery bleedings are potentially fatal injuries. Apart from conservative and surgical treatment options, emergency interventional radiological treatment can also be performed. We report our experience with emergency intercostal artery embolisation. Materials and Methods Patients with acute arterial bleedings from the intercostal artery who were treated interventionally over a period of 7 years were identified retrospectively. Technical and clinical success, clinical and procedural parameters as well as overall survival were analysed. Results Between 2010 and 2017, a total of 27 embolisation procedures was performed in 24 patients (14 male, mean age 65.7 ± 13.9 years). The majority of patients suffered from iatrogenic intercostal artery bleedings (n = 17; 70.1%; especially after thoracocentesis). In five cases, thoracoscopic surgery was attempted prior to intervention but was unsuccessful. Primary technical success was obtained in 25/27 interventions. In two cases, there was re-bleeding via collateral arteries so that re-intervention became necessary (secondary technical success). In 15 cases, secondary surgery after successful interventional treatment was necessary to evacuate the haematoma/haemothorax. Intercostal artery embolisation was clinically successful in 23/24 patients. One patient died despite technically successful embolisation, due to extensive haemothorax. One case of spinal ischaemia was observed as a major complication. Conclusion Intercostal artery embolisation is an effective interventional radiological emergency measure in patients with acute bleeding and is an alternative to surgical treatment even after attempted, unsuccessful surgery. Because of potentially severe complications, the interventional procedure should be performed by an experienced interventionalist.

Incidence and risk factors of early arterial blood flow stasis during first radioembolization of primary and secondary liver malignancy using resin microspheres: an initial single-center analysis.

OBJECTIVES: To retrospectively determine incidence of early arterial blood flow stasis and its influencing factors during resin-based radioembolization (RE) of liver tumours. METHODS: Data of patients undergoing resin-based RE from 06/2006-12/2013 were reviewed. Second RE procedures of the same liver lobe were excluded. 90-yttrium dose was calculated according to the body surface area method. Data were categorized according to RE without full dose application because of early stasis and with full dose application. Clinical/procedural characteristics were recorded. Logistic regression was performed to identify associations between clinical/procedural characteristics and early stasis. RESULTS: 362 patients [220 male; mean age 62 years (range 26-90)] underwent 416 RE sessions with early stasis occurring in 103 REs (24.8 %). Highest incidence and degree of stasis were observed in breast cancer metastases [42.6 % (20/47); 55.8 % of mean intended dose administered]. Independent risk factors were: metastasized breast cancer (odds ratio [OR] 2.18, p = 0.02), liver tumour-burden <25 % and 25-50 % (ORs 5.33, 15.64; p < 0.0001), tumour hypovascularity (OR 2.70, p = 0.04), previous bevacizumab therapy (OR 2.79, p = 0.0009) and concurrent chemotherapy (OR 8.69, p < 0.0001). CONCLUSION: Early stasis was observed in 24.8 % of resin-based REs. In the presence of the identified risk factors, extra care should be taken during microsphere administration. KEY POINTS: • Early arterial blood flow stasis is a known problem of resin-based RE. • The study showed that early stasis occurs in 25 % of REs. • Several clinical and procedural factors are associated with early stasis. • In patients at risk extra care should be taken during RE.

Intravoxel Incoherent Motion Diffusion-Weighted MR Imaging for Prediction of Early Arterial Blood Flow Stasis in Radioembolization of Breast Cancer Liver Metastases.

PURPOSE: To retrospectively evaluate predictive value of intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) for early arterial blood flow stasis during transarterial radioembolization (TARE) of liver dominant breast metastases (LdBM). MATERIALS AND METHODS: Preinterventional 1.5T DWI (b0, b1, b2 = 0, 50, 800 s/mm(2)) data for 28 liver lobes of 18 female patients treated by resin-based radioembolization (10 bilobar and 8 unilobar treatments) were analyzed. Apparent diffusion coefficient (ADC) (0, 800) and an estimation of the true diffusion coefficient D' and of the perfusion fraction f' were calculated for the 2 largest metastases. Response rate at 3 months and survival were analyzed. Procedures without full dose application because of early stasis were assigned to group A (n = 15), and procedures with full dose application were assigned to group B (n = 13). RESULTS: Metastases in group A showed significantly lower f' (0.035 ± 0.018 vs 0.076 ± 0.015, P < .0001) and a trend toward lower ADC(0, 800) with values given in 10(-6) mm(2)/s (1,066 ± 141 vs 1,189 ± 176, P = .051); no group difference was shown for D'. Groups were best discriminated by weighted mean f' values of the 2 largest metastases with accuracy of 100%. Mean tumor diameter before and after TARE was 51 mm ± 18 and 50 mm ± 24 in group A and 47 mm ± 27 and 48 mm ± 32 for group B. Imaging response did not differ between groups (P = .545). Overall survival did not differ significantly between group A (230 d) and B (155 d) (P = .124). CONCLUSIONS: Perfusion-sensitive IVIM parameter f' may predict early blood flow stasis in patients undergoing TARE for LdBM. Determination of this parameter before intervention may increase awareness of the interventionalist and increase safety of microsphere administration.

Yttrium-90 Radioembolization of Advanced, Unresectable Breast Cancer Liver Metastases-A Single-Center Experience.

PURPOSE: To determine value of transarterial radioembolization (TARE) for palliative treatment of unresectable liver-dominant breast metastases (LdBM) and to determine prognostic parameters. MATERIALS AND METHODS: Records of patients undergoing TARE for progressing LdBM between June 2006 and March 2015 were retrospectively reviewed; 44 female patients (mean age 56.1 y; range, 34.9-85.3 y) underwent 69 TAREs (56 resin-based, 13 glass-based). Of 44 patients, 42 had bilobar disease. Mean administered activity was 1.35 GBq ± 0.71. Median clinical and imaging follow-up times were 121 days (range, 26-870 d; n = 42 patients) and 93 days (range, 26-2,037 d; n = 38 patients). Clinical and biochemical toxicities, imaging response (according to Response Evaluation Criteria In Solid Tumors), time to progression, and overall survival (OS) were evaluated. Data were analyzed with stratification according to clinical and procedural parameters. RESULTS: Toxicities included 1 cholecystitis (grade 2) and 1 duodenal ulceration (grade 3); no grade ≥ 4 clinical toxicities were noted. Objective response rate (complete + partial response) was 28.9% (11/38); disease control rate (response + stable disease) was 71.1% (27/38). Median time to progression of treated liver lobe was 101 days (range, 30-2,037 d). During follow-up, 34/42 patients died (median OS after first TARE: 184 d [range 29-2,331 d]). On multivariate analysis, baseline Eastern Cooperative Oncology Group (ECOG) status of 0 (P < .0001, hazard ratio [HR] = 0.146) and low baseline γ-glutamyltransferase (GGT) levels (P = .0146, HR = 0.999) were predictors of longer OS. CONCLUSIONS: TARE can successfully delay progression of therapy-refractory LdBM with low complication rate. Nonelevated baseline ECOG status and low GGT levels were identified as prognostic factors.

Postinterventional passive expansion of partially dilated transjugular intrahepatic portosystemic shunt stents.

PURPOSE: To investigate passive transjugular intrahepatic portosystemic shunt (TIPS) stent expansion in patients with intentional "underdilation" (eg, 10-mm stent, 8-mm balloon) during TIPS creation. MATERIALS AND METHODS: Custom in-house software was developed for objective quantification of cross-sectional stent area from computed tomography (CT) data. The technique was validated by in vitro experiments. The study included 39 patients (22 men; mean age, 59.2 y) who underwent TIPS creation (VIATORR stent graft [W. L. Gore & Associates, Flagstaff, Arizona]; n = 29; WALLSTENT endoprosthesis [Boston Scientific, Marlborough, Massachusetts], n = 10) with stent underdilation. Follow-up CT data of the patients were used to quantify in vivo stent area changes. Data were analyzed by variance analysis and entered into a general linear model to test for interrelations between stent area changes and clinical (eg, cirrhosis grade) and procedural parameters. RESULTS: In vitro validation of the in-house software showed good agreement and reproducibility without overestimation of stent area. Mean clinical follow-up time in patients was 787 days (range, 7-2,450 d). At the time of intervention, VIATORR stent grafts and WALLSTENT endoprostheses were dilated to an average of 64.4% ± 2.3% and 65.63% ± 8.52% of nominal area, respectively. At the last imaging follow-up evaluation, this value had increased in all stents to a mean of 87.8% ± 7.9% (VIATORR) and 82.34% ± 19.6% (WALLSTENT) in the TIPS tract (P < .05). Multivariate analysis revealed the time after intervention to be the only predictor of stent area in the TIPS tract. There was no significant association between stent expansion and clinical or procedure-related parameters. CONCLUSIONS: The area of self-expanding stents implanted in the liver for TIPS creation with dilation to less than nominal diameter significantly increases over time. This increase has to be considered as an additional factor influencing the long-term portosystemic gradient.

Feasibility of temporary protective embolization of normal liver tissue using degradable starch microspheres during radioembolization of liver tumours.

PURPOSE: To describe a new approach to protect nontarget healthy liver tissue using degradable starch microspheres (DSM) as a short-term embolizate during radioembolization of liver tumours with (90)Y microspheres. METHODS: Between December 2011 and July 2012 radioembolization was performed in 54 patients. Five of these patients (three women, two men; mean age 67 years) underwent protective temporary embolization using DSM (EmboCept® S) of normal liver tissue that could not be excluded from the area treated by radioembolization through catheter repositioning. Clinical symptoms, laboratory findings, preinterventional imaging, and (99m)Tc-MAA and bremsstrahlung SPECT/CT, as well as baseline and follow-up imaging with (18)F-FDG PET/CT and MRI, were evaluated in relation to the technical and clinical success of the protective embolization. RESULTS: Temporary embolization of arteries supplying normal liver tissue using DSM was technically successful in all five patients. (99m)Tc-MAA SPECT/CT performed in the first two patients after DSM injection showed no increased pulmonary shunting compared to the MAA test injection without DSM. Bremsstrahlung SPECT/CT after radioembolization demonstrated satisfactory irradiation of the tumour and successful protection of normal liver tissue. There were only mild hepatotoxic effects (grade 1) on laboratory follow-up examinations, and no adverse events associated with DSM embolization or radioembolization were recorded. CONCLUSION: Temporary embolization with DSM before radioembolization is feasible and can effectively protect areas of normal liver tissue from irradiation and avoid permanent embolization if other methods such as catheter repositioning are not possible due to the location of the metastases.

Radiographic evaluation of ventral instability in lumbar spondylolisthesis: do we need extension radiographs in routine exams?

PURPOSE: To determine the usefulness of acquiring extension radiographs for the evaluation of the degree of spondylolisthesis. METHODS: Routine radiographs of the lumbar spine were retrospectively evaluated in 87 patients (mean-age 63, range 32-86) by two independent radiologists. All patients received radiographs in standing neutral, flexion and extension position. Vertebral body depth, sagittal translational displacement and lordosis angle were measured and slip percentage (SP) was calculated on standing neutral, flexion and extension radiographs. Statistical analysis was performed with a two-sided t test. Inter- and intraobserver reliability was assessed using the kappa-coefficient. RESULTS: There was no statistically significant SP-difference between neutral standing and extension images. Ventral instability was diagnosed in 25-34 % (cut-off >8 % SP-difference) for neutral versus flexion comparison. The detection rate of flexion-extension radiographs representing the extremes of motion was lower with 15-22 %. Inter- and intraobserver reliability was good to excellent. CONCLUSION: Slip percentage in routine standing extension radiography ultimately does not differ from that obtained in a static neutral standing view. Extension radiography may therefore be omitted in a routine work-up of ventral instability in lumbar spondylolisthesis.