Long-term results and comparison of flow re-direction endoluminal device and pipeline embolization device in endovascular treatment of intracranial carotid aneurysms.

OBJECTIVE: This study aims to compare the efficacy, safety, and long-term outcomes of two flow diverters, i.e., pipeline embolization device and flow re-direction endoluminal device, in the treatment of distal carotid aneurysms. METHODS: A total of 138 patients with 175 aneurysms were included from February 2012 to September 2019. Ninety-nine aneurysms were treated with flow re-direction endoluminal device and 76 with pipeline embolization device. Angiographic follow-ups were at the 6th, 12th, 24th, 36th, and 60th months; the O'Kelly-Marotta grading scale was used to assess aneurysms occlusion. Outcomes of two devices were compared; possible associations regarding patient characteristics, aneurysm properties, treatment details, and adverse events were evaluated. RESULTS: The mean follow-up period was 33 months, with 10 patients lost to follow-up. Occlusion rates at the 6th and 12th months and during the last follow-up were similar for flow re-direction endoluminal device (81%, 84%, and 90%) and pipeline embolization device (82%, 85%, and 93%). Occlusion rates were also similar after stand-alone use without coiling. There was no significant difference regarding adverse event rates with a 10.9% overall complication rate, 3.6% mortality, and 0.7% permanent morbidity. All the mortality and morbidity were related to hemorrhagic complications. Device deployment failure was observed with five flow re-direction endoluminal devices and two pipeline embolization devices, whereas two severe in-stent stenoses occurred with each device. CONCLUSIONS: Both flow re-direction endoluminal device and pipeline embolization device are feasible and effective in flow diversion of distal internal carotid artery aneurysms, with similar adverse events rates and aneurysm occlusion success. Aneurysm occlusion rates increase with time, while the presence of an integrated branch significantly decreases treatment success.

Intravoxel Incoherent Motion Parameters for Assessing the Efficiency of Locoregional Bridging Treatments before Liver Transplantation.

OBJECTIVE: To evaluate the diagnostic accuracy of Intravoxel Incoherent Motion (IVIM) parameters for assessment of tumor response after locoregional treatment (LRT) of hepatocellular carcinoma (HCC). METHODS: Fifteen patients with HCC who had undergone LRTs (11 transarterial radioembolization, 4 transarterial chemoembolization) were included. In addition to routine upper abdominal magnetic resonance imaging sequences, IVIM with 16 different b values and conventional diffusion weighted imaging with 3 different b factors were obtained immediately before and 8 weeks after LRTs. Magnetic resonance imaging response was evaluated according to modified Response Evaluation Criteria in Solid Tumors (mRECIST) and HCCs were categorized into 2 subgroups, responders and nonresponders. Quantitatively, the number of diffusion-changes were calculated with apparent diffusion coefficient (ADC) and IVIM parameters, including mean D (true diffusion coefficient), pseudo-diffusion coefficient associated with blood flow, and f (perfusion fraction) values. Subsequently, the pre- and post-treatment parameters were compared using the Mann-Whitney U test. RESULTS: Considering all HCCs, a significant decrease was observed according to mRECIST criteria (-38.43 ± 16.49). The ADC and D values after LRTs were significantly higher than those of the preceding ones. The f values after LRTs were significantly lower than those of pre-treatment. In the responders group, ADC and D values were significantly increased and f values were significantly decreased after LRTs. No difference of statistical significance was achieved in the nonresponders group. CONCLUSIONS: ADC values and IVIM parameters appear to reflect the response of LRTs as effectively as those of mRECIST. This promises new horizons in the management of pretransplant patients, especially in renal insufficiency clinical settings, owing to the elimination of contrast media administration.

Value of Intravoxel Incoherent Motion for Hepatocellular Carcinoma Grading.

BACKGROUND: To evaluate the diagnostic accuracy of intravoxel incoherent motion (IVIM) parameters in estimation of hepatocellular carcinoma (HCC) grading. MATERIALS AND METHODS: Twenty-nine patients with histopathologically diagnosed as 42 HCC at explant were included in this retrospective study. All patients were examined by 1.5T magnetic resonance imaging with the use of 4-channel phased array body coil. In addition to routine pre- and postcontrast sequences, IVIM (16 different b factors varying from 0 to 1300 s/mm2) and conventional diffusion-weighted imaging (3 different b factors of 50, 400, 800 s/mm2) were obtained with single-shot echo planar spin echo sequence. Apparent diffusion coefficient (ADC) and IVIM parameters including mean D (true diffusion coefficient), D* (pseudo-diffusion coefficient associated with blood flow), and f (perfusion fraction) values were calculated. Histopathologically, HCC was classified as low (grade 1, 2) and high (grade 3, 4) grade in accordance with the Edmondson-Steiner score. Quantitatively, ADC, D, D*, and f values were compared between the low- and high-grade groups by Student t test. The relationship between the parameters and histologic grade was analyzed using the Spearman's correlation test. To evaluate the diagnostic performance of the parameters, receiver operating characteristic analysis was performed. RESULTS: High-grade HCCs had significantly lower ADC and D values than low grade groups (P = .005 and P = .026, retrospectively); ADC and D values were inversely correlated with tumor grade (r = -0.519, P = .011, r = -0.510, P = .026, respectively). High-grade HCCs had significantly higher f values when compared with the low-grade group (P = .005). The f values were positively correlated with tumor grade (r = 0.548, P = .007). The best discriminative parameter was f value. Cut-off value of 32% of f values showed sensitivity of 75.6% and a specificity of 73.5%. CONCLUSION: ADC values and IVIM parameters such as f values appear to reflect the grade of HCCs.

Novel Application of Internal-External Drainage Catheter as Biliary Stent for Percutaneous Transhepatic Treatment of Biliary Strictures in Living Donor Liver Transplantation Recipient Patients.

OBJECTIVES: Although endoscopic management is considered as the first-line treatment for biliary strictures, it may be challenging in living donor liver transplant recipients due to the complex nature of duct-to-duct reconstruction. In this study we present the use of a pigtail drainage catheter as a biliary stent to treat biliary strictures after a living donor liver transplant. METHODS: Twenty-seven patients with biliary strictures were treated with our novel technique. In this technique, a pigtail catheter was trimmed into 3 parts (proximal, middle, and distal portions). A suture string was passed through the distal hole of the middle portion, which was then reversed and used as a stent while the proximal portion was used as a pusher. Following balloon dilation of the stenotic segment, the distal, reversed middle, and proximal portions were loaded over the guidewire. After proper placement of the stent, the retractor suture string, pusher, and guidewire were removed. The stent was removed during the third or fourth month of placement through endoscopic retrograde cholangiopancreatography (ERCP) in all patients. RESULTS: No significant complications developed during the procedure or follow-up period. Ten patients required re-stenting by ERCP during the same session. The mean follow-up period was 2 years. Cholestase enzymes and bilirubin levels were within normal limits in all patients during follow-up. CONCLUSION: Stents derived from drainage catheter facilitate treatment of biliary strictures in patients not eligible for the retrograde approach. This stent is cheap, easy to implement, can be easily removed by ERCP, and re-stenting can be applicable in retrograde if needed.

Value of Imaging Findings in the Prediction of Microvascular Invasion in Hepatocellular Carcinoma.

BACKGROUND: The purpose of this study was to determine the utility of some imaging findings in predicting microvascular invasion (MVI) and hepatocellular carcinoma (HCC) recurrence risk after liver transplantation. METHOD: This retrospective study included 123 patients with histopathologically proven HCC at explant. All HCCs were classified as MVI positive (group I) or negative (group II) based on histopathological findings. In each group, multifocality, largest tumor size, bulging (tumor causing liver capsule expansion), beak sign (the acute angle between the tumor and liver parenchyma), and diffusion restriction on diffusion weighted images (DWI) were evaluated. These findings were compared between the groups by Student's t test. The relation between the parameters and MVI was analyzed by using the Spearman's correlation test. RESULTS: Of the total patients, 30.1% had MVI (group I) and 69.9% (group II) did not have MVI. Presence of beak sign (P ≤ .005), bulging sign (P = .002), and diffusion restriction (P = .045) were significantly more frequent in group I than group II. The beak sign, bulging sign, and diffusion restriction were correlated with presence of MVI. Largest tumor size and multifocality were higher in group I than group II, but the differences were not statistically significant. CONCLUSION: Radiologists and transplant surgeons should be aware of some clue imaging findings, especially beak and bulging signs because these findings may predict the presence of MVI in HCC. These patients might benefit from histologic confirmation of the tumor characteristics through biopsy and subsequent bridging treatment options before liver transplantation to reduce the risk of recurrence.

Stent-assisted coil embolization of challenging intracranial aneurysms: initial and mid-term results with low-profile ACCLINO devices.

BACKGROUND: Stent-assisted coiling using low-profile, self-expandable and retrievable stents is a valid option in endovascular treatment of challenging intracranial aneurysms. This study aims to evaluate the feasibility and efficacy of ACCLINO 1.9 F and ACCLINO Flex stent systems, designed for use as adjunctive products in coil embolization of intracranial aneurysms. METHODS: Case files of 47 patients, and 52 aneurysms in total, treated with at least one ACCLINO 1.9 F or ACCLINO Flex stent were retrospectively evaluated. Technical success, complications, and angiographic outcomes were assessed based on immediate post-procedural controls along with 6th and 12th month angiograms. RESULTS: Mechanical untoward event rate, including asymptomatic complications, is 9.6 % (five out of 52 aneurysms). Failed dual-stenting attempt rate is 15.4 % (two out of 13). Overall procedure-related morbidity is 4.2 % with no neurologic sequelae. Initial occlusion rate is 90.4 % (47 aneurysms). One patient had residual filling in the aneurysm neck, which was stable throughout follow-up. The remaining four cases had spontaneous follow-up occlusion. Recanalization rate at 6th month is 2.1 % with one aneurysm requiring retreatment. One patient was lost to follow-up. There is no mortality associated with treatment. CONCLUSIONS: Stent-assisted coil embolization with ACCLINO stents in single or dual configurations is a feasible treatment option for challenging intracranial aneurysms. Follow-up results are encouraging; techniques were effective in complex cases and there were no clinically significant adverse outcomes.