Portal Vein Recanalization for Noncirrhotic Portal Vein Cavernous Transformation: Transjugular Intrahepatic Portosystemic Shunt Creation versus Portal Vein Stent Placement

PurposeTo compare the clinical outcomes of transjugular intrahepatic portosystemic shunt (TIPS) creation versus portal vein stent placement (PVS) in patients with noncirrhotic cavernous transformation of the portal vein (CTPV).Materials and MethodsIn this retrospective study, clinical data from patients with noncirrhotic CTPV who underwent TIPS creation or PVS were compared. A total of 54 patients (mean age, 43.8 years ± 15.8; 31 men and 23 women) were included from January 2013 to January 2021; 29 patients underwent TIPS creation, and 25 patients underwent PVS. Stent occlusion, variceal rebleeding, survival, and postprocedural complications were compared between the 2 groups.ResultsThe mean follow-up time was 40.2 months ± 26.2 in the TIPS group and 35.3 months ± 21.1 in the PVS group. The stent occlusion rate in the PVS group (16%, 4 of 25) was significantly lower than that in the TIPS group (41.4%, 12 of 29) during the follow-up (P = .042). The cumulative variceal rebleeding rates in the TIPS group were significantly higher than those in the PVS group (28% vs 4%; P = .027). The procedural success rate was 69% in the TIPS group and 86% in the PVS group (P = .156). There was a higher number of severe adverse events after TIPS than after PVS (0% vs 24%; P = .012).ConclusionsPortal vein recanalization with PVS may be a preferable alternative to TIPS creation in the treatment of noncirrhotic CTPV because of higher stent patency rates, lower risk of variceal rebleeding, and fewer adverse events.     

Prospective Comparison of Freehand and Electromagnetic Needle Tracking for US-guided Percutaneous Liver Biopsy

PurposeTo prospectively compare electromagnetic needle tracking (EMT) and freehand ultrasound (US)-guided liver biopsies.Materials and MethodsAmong 60 consecutive US-guided liver biopsies performed by staff radiologists (senior operators) and residents (junior operators), 30 were performed freehand and 30 with EMT. Needle placement time, numbers of needle punctures and pullbacks, and subjective scores of procedure difficulty were compared by χ² or Student t test.ResultsDiagnostic success rates, defined by the procurement of an adequate histopathologic specimen, were 96.6% for freehand biopsy and 100% with EMT. Needle placement time was significantly lower for EMT (mean ± standard deviation, 45.8 s ± 48.1) than for freehand procedures (143.2 s ± 122.1; P < .01). In the freehand group, needle placement times were 179.6 seconds ± 133.3 for junior operators and 106.8 seconds ± 101.3 for senior operators (P = .15). In the EMT group, needle placement times were 49.2 seconds ± 55 for junior operators and 42.5 seconds ± 41.2 for senior operators (P = .53). The number of needle pullbacks was significantly lower for senior operators (1.2 ± 0.80) compared with junior operators (2.4 ± 1.4) in the freehand group (P = .01), with no significant difference (junior, 0.47 ± 0.92; senior, 0.67 ± 0.72; P = .24) in the EMT group. The postprocedural difficulty score was lower in the EMT group (1.5 ± 0.7) than in the freehand group (2.1 ± 1.1; P = .02). Needle placement time and number of needle pullbacks were lower in the EMT group, even after taking into account tumor size and depth and operator experience.ConclusionsThe EMT procedure shortens needle placement time and reduces the number of needle pullbacks needed for redirection, regardless of operator experience.     

Three-dimensional C-arm CT-guided transjugular intrahepatic portosystemic shunt placement: Feasibility,technical success and procedural time

Objectives

Establishment of transjugular intrahepatic portosystemic shunts (TIPS) constitutes a standard procedure in patients suffering from portal hypertension. The most difficult step in TIPS placement is blind puncture of the portal vein. This study aimed to evaluate three-dimensional mapping of portal vein branches and targeted puncture of the portal vein.

Methods

Twelve consecutive patients suffering from refractory ascites by liver cirrhosis were included in this retrospective study to evaluate feasibility, technical success and procedural time of C-arm CT-targeted puncture of the portal vein. As a control, 22 patients receiving TIPS placement with fluoroscopy-guided blind puncture were included to compare procedural time.

Results

Technical success could be obtained in 100 % of the study group (targeted puncture) and in 95.5 % of the control group (blind puncture). Appropriate, three-dimensional C-arm CT-guided mapping of the portal vein branches could be achieved in all patients. The median number of punctures in the C-arm CT-guided study group was 2?±?1.3 punctures. Procedural time was significantly lower in the study group (14.8?±?8.2 min) compared to the control group (32.6?±?22.7 min) (p?=?0.02).

Conclusions

C-arm CT-guided portal vein mapping is technically feasible and a promising tool for TIPS placement resulting in a significant reduction of procedural time.

Key Points

? C-arm CT-mapping of the portal vein for 3D TIPS guidance is feasible. ? Targeted punctures of the portal vein by C-arm CT reduce procedural time. ? A decreased number of punctures could improve patient safety.

     

Acoustic radiation force impulse (ARFI) in the evaluation of the renal parenchymal stiffness in paediatric patients with vesicoureteral reflux: preliminary results

Objectives

To prospectively evaluate acoustic radiation force impulse (ARFI) imaging of the kidneys in children with and without chronic renal disease.

Methods

Twenty-eight children (age range 9–16 years) with primary or secondary vesicoureteral reflux (≥ grade III) underwent scintigraphy and ultrasound with ARFI. Kidneys were divided—according to scintigraphy—into “affected” and “contralateral”; the results were compared with 16 age-matched healthy subjects. An ARFI value, expressed as speed (m/s) of wave propagation through the tissue, was calculated for each kidney through the mean of the values obtained at the upper, middle and lower third. The Wilcoxon test was used; P values <0.05 were considered statistically significant.

Results

The mean ARFI values obtained in the “affected” kidneys (5.70?±?1.71 m/s) were significantly higher than those measured in both “contralateral” (4.09?±?0.97, P?<?0.0001) and “healthy” kidneys (3.13?±?0.09, P?<?0.0001). The difference between values in the “contralateral” kidneys and “healthy” ones was significant (P?<?0.0001). The “affected” kidneys with secondary reflux had mean ARFI values (6.59?±?1.45) significantly higher than those with primary reflux (5.35?±?1.72).

Conclusions

ARFI values decrease from kidneys with secondary vesicoureteral reflux to kidneys with primary reflux to unaffected kidneys contralateral to reflux to normal kidneys.

Key points

? Acoustic radiation force impulse (ARFI) can quantify tissue elasticity during ultrasound examinations. ? Kidneys are highly heterogeneous and difficult to evaluate with ARFI. ? Kidneys damaged by vesicoureteral reflux are stiffer than normal. ? ARFI can identify initial damage in macroscopically normal kidneys.     

Portal hypertension correlates with splenic stiffness as measured with MR elastography

Purpose:

To investigate the correlation between MR elastography (MRE) assessed spleen stiffness and direct portal vein pressure gradient (D‐HVPG) measurements in a large animal model of portal hypertension.

Materials and Methods:

Cholestatic liver disease was established in adult canines by common bile duct ligation. A spin echo based echo planar imaging (EPI) MRE sequence was used to acquire three‐dimensional/three axis (3D/3‐axis) abdominal MRE data at baseline, 4 weeks, and 8 weeks. Liver biopsies, blood samples, and D‐HVPG measurements were obtained simultaneously.

Results:

Animals developed portal hypertension (D‐HVPG: 11.0 ± 5.1 mmHg) with only F1 fibrosis after 4 weeks. F3 fibrosis was confirmed after 8 weeks despite no further rise in portal hypertension (D‐HVPG: 11.3 ± 3.2 mmHg). Mean stiffnesses of the spleen increased over two‐fold from baseline (1.72 ± 0.33 kPa) to 4 weeks (3.54 ± 0.31 kPa), and stabilized at 8 weeks (3.38 ± 0.06 kPa) in a pattern consistent with changes in portal pressure. A positive correlation was observed between spleen stiffness and D‐HVPG (r² = 0.86; P < 0.01).

Conclusion:

These findings indicate a temporal relationship between portal hypertension and the development of liver fibrosis in a large animal model of cholestatic liver disease. The observed direct correlation between spleen stiffness and D‐HVPG suggest a noninvasive MRE approach to diagnose and screen for portal hypertension. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.     

Impact of Portal Hypertension on Adverse Events after Splenic Arterial Aneurysm Embolization

PurposeTo evaluate the outcomes of splenic artery aneurysm (SAA) embolization and compare adverse event (AE) rates after embolization in patients with and without portal hypertension (PHTN).Materials and MethodsA retrospective review of all patients who underwent embolization of SAAs at 2 institutions was performed (34 patients from institution 1 and 7 patients from institution 2). Baseline demographic characteristics, preprocedural imaging, procedural techniques, and postprocedural outcomes were evaluated. Thirty-day postprocedural severe and life-threatening AEs were evaluated using the Society of Interventional Radiology guidelines. Thirty-day mortality and readmission rates were also evaluated. t test, χ² test, and/or Fisher exact test were used for the statistical analysis.ResultsThere was no statistically significant difference between patients with and without PHTN in the location, number, and size of SAA(s). All procedures were technically successful. There were 13 (32%) patients with and 28 (68%) patients without PHTN. The 30-day mortality rate (31% vs 0%; P = .007), readmission rates (61% vs 7%; P < .001), and severe/life-threatening AE rates (69% vs 0%; P < .001) were significantly higher in patients with PHTN than in those without PHTN.ConclusionsThere was a significantly higher mortality and severe/life-threatening AE rate in patients with PHTN than in those without PHTN. SAAs in patients with PHTN need to be managed very cautiously, given the risk of severe/life-threatening AEs after embolization.     

Transjugular Intrahepatic Portosystemic Shunt Creation Using a Radiofrequency Wire: Prospective Clinical Safety and Feasibility Trial in Cirrhosis

PurposeTo assess the safety and feasibility of using a radiofrequency (RF) wire for portosystemic shunt creation.Materials and MethodsTen patients undergoing elective creation of a transjugular intrahepatic portosystemic shunt (TIPS) or a direct intrahepatic portosystemic shunt (DIPS) were prospectively enrolled. Primary outcomes were the safety and feasibility of RF wire used for the creation of TIPS and DIPS. Median age was 66.5 ± 6.1 years. Causes of liver disease included alcohol (n = 5), nonalcoholic steatohepatitis (n = 2), hepatitis C virus (n = 1), primary biliary cirrhosis (n = 1), autoimmune hepatitis (n = 1). The median score for model for end-stage liver disease was 11 ± 4.3. The Rosch-Uchida TIPS set was used with intravascular ultrasonography guidance in all cases. A 0.035-inch RF wire was used in lieu of the trocar needle through the 5-F TIPS set catheter to create a track between the hepatic vein and the portal vein. All shunts were created using stent grafts.ResultsTechnical success rate was 100%. In 7 of 10 patients, portal vein access was achieved with a single pass. A DIPS was created in 2 patients based on anatomic favorability. Median fluoroscopy time was 13.3 ± 3.8 min, and median total procedure time was 102 ± 19 min. The wire passed through parenchyma without subjective deflection. There was 1 case of extracapsular puncture with no clinical consequence. The RF wire was too stiff to curve into the main portal vein, requiring wire exchange in all but 1 case. Mean portosystemic gradient decreased from 13.9 ± 3.3 to 5.9 ± 2.1 mm Hg. No immediate complications were encountered. Shunt patency was 100% at 30 days.ConclusionsCreation of TIPS and DIPS using an RF wire was safe and feasible, enabling creation of an intrahepatic track without subjective deflection in cirrhotic patients.     

The effects of eccentric hamstring strength training on dynamic jumping performance and isokinetic strength parameters: a pilot study on the implications for the prevention of hamstring injuries

ObjectivesAlthough previous research shows that the hamstring length–tension relationship during eccentric contractions plays a role in hamstring injury, training methods to promote beneficial adaptations are still unclear. The purpose of this pilot study was to determine whether an eccentric hamstring specific training programme results in favourable adaptations.DesignEccentric training consisting of the Nordic hamstring exercise performed twice a week for four weeks. Pre- and post-training concentric/concentric isokinetic testing of peak torque (PT) and position of peak torque (POS) was performed for both the quadriceps and hamstrings of both legs at 60° s⁻¹. Vertical jump height was also assessed.ParticipantsNine athletic, male subjects with no previous strength training experience.ResultsThere was a significant increase in vertical jump height (pre=51.0±4.8 cm, post=54.4±6.3 cm, p=0.04), a significant reduction in quadriceps PT (pre=204.6±21.9 N.m., post=181.5±19.9 N.m., p=0.01), a significant decrease in hamstring POS from full knee extension (pre=32.5±7.4°, post=26.2±8.6°, p=0.01) and a significant hamstring POS difference between limbs (dominant=33.8±9.5°, non-dominant=24.9±6.5°, p=0.01).ConclusionNordic hamstring exercise training may produce favourable neuromuscular adaptations for the possible prevention of hamstring injuries while enhancing performance in athletic, untrained males.     

Assessment of liver steatosis in chicken by using acoustic radiation force impulse imaging: preliminary results

Objective

To evaluate acoustic radiation force impulse (ARFI) imaging as a non-invasive tool for quantification of the grades of liver steatosis in chickens.

Methods

We used two different diets: a standard diet (SD group) and a hyperlipidaemic diet (HD group). The ARFI technique was performed in all the animals in the right hepatic lobe and shear wave velocity (SWV) was measured and expressed in metres per second (m/s). Plasma lipid levels were analysed. Steatosis was quantified by using semiquantitative analysis. Statistical analysis was used and Pearson’s correlation coefficient was calculated.

Results

Mean SWV was 0.94?±?0.16 m/s (range 0.8–1.3 m/s) in the SD group and 1.91?±?0.25 m/s (range 1.3–2.2 m/s) in the HD group (p?<?0.001). The lowest SWVs (≤1.3 m/s) corresponded to the chickens in the SD group, with 100% of the animals returning a score of 0, whereas the range of SWV in the HD group chickens was between 1.6 and 2.2 m/s. A substantial correlation was observed between SWVs with histological semiquantitative analysis of steatosis (r?=?0.85, p?<?0.001).

Conclusion

ARFI imaging is a non-invasive diagnostic tool that allows discrimination between the grades of liver steatosis in chickens.     

Repeated Percutaneous Radiofrequency Ablation for Hepatocellular Carcinoma in Patients with Cirrhosis: Assessment of Safety Based on Liver Function and Portal Hypertension Parameters

PurposeTo evaluate changes in liver function and portal hypertension parameters after repeated percutaneous radiofrequency (RF) ablation for hepatocellular carcinoma (HCC) in patients with cirrhosis.Materials and MethodsThis study included 24 patients (male-to-female ratio, 15:9; mean age, 59.4 y) with early-stage HCC (mean tumor size, 1.91 cm) and cirrhosis who underwent three consecutive treatments with RF ablation between April 1999 and August 2011. Serial changes of liver function and portal hypertension parameters after repeated RF ablation were compared with baseline values using a mixed model and Wilcoxon signed rank test.ResultsThe interval between the first and second RF ablation measurements and between the second and third RF ablation measurements was 26.1 months ± 18.3 (range, 3.8–65.8 mo) and 16.6 months ± 9.8 (range, 4.7–35.4 mo), respectively. Total bilirubin level was significantly increased between the first RF ablation and 6 months after the third RF ablation (0.75 g/dL ± 0.37 to 1.06 g/dL ± 0.68, P = .001), but all values were within the normal range. No other liver function parameter showed a significant change (P > .05 for all). Portal hypertension parameters did not show significant changes between the first RF ablation and 6 months after the third RF ablation (P > .05).ConclusionsRepeated RF ablation for controlling recurrent HCC did not seem to affect liver function and portal hypertension in patients.     

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.

Toward MR-guided high intensity focused ultrasound for presurgical localization: focused ultrasound lesions in cadaveric breast tissue

Purpose:

To investigate magnetic resonance image‐guided high intensity focused ultrasound (MR‐HIFU) as a surgical guide for nonpalpable breast tumors by assessing the palpability of MR‐HIFU‐created lesions in ex vivo cadaveric breast tissue.

Materials and Methods:

MR‐HIFU ablations spaced 5 mm apart were made in 18 locations using the ExAblate2000 system. Ablations formed a square perimeter in mixed adipose and fibroglandular tissue. Ablation was monitored using T1‐weighted fast spin echo images. MR‐acoustic radiation force impulse (MR‐ARFI) was used to remotely palpate each ablation location, measuring tissue displacement before and after thermal sonications. Displacement profiles centered at each ablation spot were plotted for comparison. The cadaveric breast was manually palpated to assess stiffness of ablated lesions and dissected for gross examination. This study was repeated on three cadaveric breasts.

Results:

MR‐ARFI showed a collective postablation reduction in peak displacement of 54.8% ([4.41 ± 1.48] μm pre, [1.99 ± 0.82] μm post), and shear wave velocity increase of 65.5% ([10.69 ± 1.60] mm pre, [16.33 ± 3.10] mm post), suggesting tissue became stiffer after the ablation. Manual palpation and dissection of the breast showed increased palpability, a darkening of ablation perimeter, and individual ablations were visible in mixed adipose/fibroglandular tissue.

Conclusion:

The results of this preliminary study show MR‐HIFU has the ability to create palpable lesions in ex vivo cadaveric breast tissue, and may potentially be used to preoperatively localize nonpalpable breast tumors. J. Magn. Reson. Imaging 2012;35:1089‐1097. © 2011 Wiley Periodicals, Inc.     

Contemporary Interventional Radiology Dosimetry: Analysis of 4,784 Discrete Procedures at a Single Institution

PurposeTo report dosimetry of commonly performed interventional radiology procedures and compare dose analogues to known reference levels.Materials and MethodsDemographic and dosimetry data were collected for gastrostomy, nephrostomy, peripherally inserted central catheter placement, visceral arteriography, hepatic chemoembolization, tunneled catheter placement, inferior vena cava filter placement, vascular embolization, transjugular liver biopsy, adrenal vein sampling, transjugular intrahepatic portosystemic shunt (TIPS) creation, and biliary drainage between June 12, 2014, and April 26, 2018, using integrated dosimetry software. In all, 4,784 procedures were analyzed. The study included 2,691 (56.2%) male subjects and 2,093 (43.8%) female subjects with mean age 55 ± 21 years (range: 0-104 years) and with mean weight of 76.9 ± 29.4 kg (range: 0.9-268.1 kg). Fluoroscopy time, dose area product (DAP), and reference dose were evaluated.ResultsTIPS had the highest mean fluoroscopy time (49.1 ± 16.0 min) followed by vascular embolization (25.2 ± 11.4 min), hepatic chemoembolization (18.8 ± 12.5 min), and visceral arteriography (17.7 ± 3.2 min). TIPS had the highest mean DAP (429.2 ± 244.8 grays per square centimeter [Gy·· cm²]) followed by hepatic chemoembolization (354.6 ± 78.6 Gy·· cm²), visceral arteriography (309.5 ± 39.0 Gy·· cm²), and vascular embolization (298.5 ± 29 Gy·· cm²). TIPS was associated with the highest mean reference dose (2.002 ± 1.420 Gy) followed by hepatic chemoembolization (1.746 ± 0.435 Gy), vascular embolization (1.615 ± 0.381 Gy), and visceral arteriography (1.558 ± 1.720 Gy). Of the six procedures available for comparison with the reference levels, the mean fluoroscopy time, DAP, and reference dose for each procedure were below the proposed reference levels.ConclusionAdvances in image acquisition technology and radiation safety protocols have significantly reduced the radiation exposure for a variety of interventional radiology procedures.     

Idarubicin-Loaded ONCOZENE Drug-Eluting Bead Chemoembolization in a Rabbit Liver Tumor Model: Investigating Safety,Therapeutic Efficacy,and Effects on Tumor Microenvironment

PurposeTo investigate toxicity, efficacy, and microenvironmental effects of idarubicin-loaded 40-μm and 100-μm drug-eluting embolic (DEE) transarterial chemoembolization in a rabbit liver tumor model.Materials and MethodsTwelve male New Zealand White rabbits with orthotopically implanted VX2 liver tumors were assigned to DEE chemoembolization with 40-μm (n = 5) or 100-μm (n = 4) ONCOZENE microspheres or no treatment (control; n = 3). At 24–72 hours postprocedurally, multiparametric magnetic resonance (MR) imaging including dynamic contrast-enhanced (DCE), diffusion-weighted imaging (DWI), and biosensor imaging of redundant deviation in shifts (BIRDS) was performed to assess extracellular pH (pHe), followed by immediate euthanasia. Laboratory parameters and histopathologic ex vivo analysis included fluorescence confocal microscopy and immunohistochemistry.ResultsDCE MR imaging demonstrated a similar degree of devascularization of embolized tumors for both microsphere sizes (mean arterial enhancement, 8% ± 12 vs 36% ± 51 in controls; P = .07). Similarly, DWI showed postprocedural increases in diffusion across the entire lesion (apparent diffusion coefficient, 1.89 × 10⁻³ mm²/s ± 0.18 vs 2.34 × 10⁻³ mm²/s ± 0.18 in liver; P = .002). BIRDS demonstrated profound tumor acidosis at baseline (mean pHe, 6.79 ± 0.08 in tumor vs 7.13 ± 0.08 in liver; P = .02) and after chemoembolization (6.8 ± 0.06 in tumor vs 7.1 ± 0.04 in liver; P = .007). Laboratory and ex vivo analyses showed central tumor core penetration and greater increase in liver enzymes for 40-μm vs 100-μm microspheres. Inhibition of cell proliferation, intratumoral hypoxia, and limited idarubicin elution were equally observed with both sphere sizes.ConclusionsNoninvasive multiparametric MR imaging visualized chemoembolic effects in tumor and tumor microenvironment following DEE chemoembolization. Devascularization, increased hypoxia, coagulative necrosis, tumor acidosis, and limited idarubicin elution suggest ischemia as the predominant therapeutic mechanism. Substantial size-dependent differences indicate greater toxicity with the smaller microsphere diameter.     

Scintigraphic evaluation of hepatic blood flow after intrahepatic portosystemic shunt (TIPS)

In patients with liver cirrhosis a transjugularly placed intrahepatic portocaval shunt (TIPS) is a non-surgical portosystemic device which aims to reduce portal venons pressure. In comparison with Doppler sonography, we evaluated in 28 patients the diagnostic impact of liver perfusion scintigraphy (with technetium-99m diethylene triamine penta-acetic acid) in the assessment of changes in the hepatic blood flow after TIPS shunting. The arterial and portal contributions to hepatic flow were calculated from the areas under the biphasic timeactivity curve. In the course of TIPS shunting, patency is threatened by reocclusion. Angiography is the gold standard for TIPS shunt reassessment. However, there is a need for a less invasive diagnostic procedure, such as scintigraphy or Doppler sonography, for the early detection of shunt insufficiency. Scintigraphy demonstrated that prior to TIPS shunting the portal venons contribution to hepatic perfusion was reduced to 29.2%, this reduction being due to portal hypertension. After TIPS placement a significant increase in portal venous perfusion was observed (38.2%;P<0.02). TIPS shunt occlusion was identified in patients by a significant reduction in the scintigraphically measured portal venons contribution to hepatic blood flow. Hepatic perfusion scintigraphy appears to be a valuable method to determine the immediate effect of TIPS on hepatic blood flow. Post-TIPS follow-up studies of hepatic haemodynamics by liver perfusion scintigraphy appear able to contribute to the detection of TIPS shunt occlusion before the clinical consequences of this complication have become apparent.     

Potential relationship between passive plantar flexor stiffness and sprint performance in sprinters

ObjectiveTo investigate the relationship between passive planter flexor stiffness and sprint performance in sprinters.DesignCross-sectional study.ParticipantsFifty well-trained male sprinters (age: 20.7 ± 1.9 years, height: 175.6 ± 4.9 cm, weight: 66.7 ± 5.1 kg) were participated in this study. Their best personal times in a 100-m sprint ranged from 10.22 to 11.86 s (mean, 11.12 ± 0.43 s).MethodsPassive stiffness of the plantar flexors measured using a dynamometer system. Passive stiffness during passive dorsiflexion was calculated from the slope of the linear portion of the torque-angle curve.ResultsPlantar flexor passive stiffness was significantly correlated with personal best 100-m sprint time (r = −0.334, P = 0.018).ConclusionThe present findings suggest that although the relationship between plantar flexor passive stiffness and personal best 100-m sprint time was relatively minimal, a higher plantar flexor passive stiffness may be a potential factor for achieving superior sprint performance in sprinters. Therefore, in the clinical setting, measurement of passive planter flexor stiffness may be useful for assessing sprint performance.     

Combined Transjugular Intrahepatic Portosystemic Shunt Plus Variceal Obliteration versus Transjugular Intrahepatic Portosystemic Shunt Alone for the Management of Gastric Varices: Comparative Single-Center Clinical Outcomes

PurposeTo compare the safety and clinical outcomes of combined transjugular intrahepatic portosystemic shunt (TIPS) plus variceal obliteration to those of TIPS alone for the treatment of gastric varices (GVs).Materials and MethodsA single-center, retrospective study of 40 patients with bleeding or high-risk GVs between 2008 and 2019 was performed. The patients were treated with combined therapy (n = 18) or TIPS alone (n = 22). There were no significant differences in age, sex, model for end-stage liver disease score, or GV type between the groups. The primary outcomes were the rates of GV eradication and rebleeding. The secondary outcomes included portal hypertensive complications and hepatic encephalopathy.ResultsThe mean follow-up period was 15.4 months for the combined therapy group and 22.9 months for the TIPS group (P = .32). After combined therapy, there was a higher rate of GV eradication (92% vs 47%, P = .01) and a trend toward a lower rate of GV rebleeding (0% vs 23%, P = .056). The estimated rebleeding rates were 0% versus 5% at 3 months, 0% versus 11% at 6 months, 0% versus 18% at 1 year, and 0% versus 38% at 2 years after combined therapy and TIPS, respectively (P = .077). There was no difference in ascites (13% vs 11%, P = .63), hepatic encephalopathy (47% vs 55%, P = .44), or esophageal variceal bleeding (0% vs 0%, P > .999) after the procedure between the groups.ConclusionsThe GV eradication rate is significantly higher after combined therapy, with no associated increase in portal hypertensive complications. This translates to a clinically meaningful trend toward a reduction in GV rebleeding. The value of a combined treatment strategy should be prospectively studied in a larger cohort to determine the optimal management of GVs.     

Feasibility of Augmented Reality–Guided Transjugular Intrahepatic Portosystemic Shunt

PurposeTo investigate an augmented reality (AR)–guided endovascular puncture to facilitate successful transjugular intrahepatic portosystemic shunt (TIPS).Materials and MethodsAn AR navigation system for TIPS was designed. Three-dimensional (3D) liver models including portal and hepatic vein anatomy were extracted from preoperative CT images. The 3D models, intraoperative subjects, and electromagnetic tracking information of the puncture needles were integrated through the system calibration. In the AR head-mounted display, the 3D models were overlaid on the subjects, which was a liver phantom in the first phase and live beagle dogs in the second phase. One life-size liver phantom and 9 beagle dogs were used in the experiments. Imaging after puncture was performed to validate whether the needle tip accessed the target hepatic vein successfully.ResultsEndovascular punctures of the portal vein of the liver phantom were repeated 30 times under the guidance of the AR system, and the puncture needle successfully accessed the target vein during each attempt. In the experiments of live canine subjects, the punctures were successful in 2 attempts in 7 beagle dogs and in 1 attempt in the remaining 2 dogs. The puncture time of needle from hepatic vein to portal vein was 5–10 s in the phantom experiments and 10–30 s in the canine experiments.ConclusionsThe feasibility of AR-based navigation facilitating accurate and successful portal vein access in preclinical models of TIPS was validated.     

Transjugular Intrahepatic Portosystemic Shunt Creation for the Prevention of Gastric Variceal Rebleeding in Patients with Hepatocellular Carcinoma: A Multicenter Retrospective Study

PurposeTo evaluate the effectiveness and safety of transjugular intrahepatic portosystemic shunt (TIPS) creation for the prevention of gastric variceal rebleeding in patients with hepatocellular carcinoma (HCC).Materials and MethodsThis multicenter retrospective study included 126 cirrhotic patients (mean age, 54.1 ± 10.2 years; 110 men) with HCC who underwent TIPS creation for the prevention of gastric variceal rebleeding. Of these, 110 (87.3%) patients had gastroesophageal varices and 16 (12.7%) patients had isolated gastric varices. Thirty-five (27.8%) patients had portal vein tumor thrombus.ResultsTIPS creation was technically successful in 124 (98.4%) patients. Rebleeding occurred in 26 (20.6%) patients during the follow-up period. The 6-week and 1-year actuarial probabilities of patients remaining free of rebleeding were 98.3% ± 1.2% and 81.2% ± 3.9%, respectively. Forty-nine (38.8%) patients died during the follow-up period. The 6-week and 1-year actuarial probabilities of survival were 98.4 ± 1.1% and 65.6 ± 4.4%, respectively. Two (1.6%) patients had major procedure-related complications, including acute liver failure (n = 1) and intra-abdominal bleeding (n = 1). Thirty-three (26.2%) patients had at least 1 episode of overt hepatic encephalopathy during the follow-up period. Shunt dysfunction occurred in 15 (11.9%) patients after a median follow-up time of 11.4 months (range, 1.4–41.3 months). Lung metastasis occurred in 3 (2.4%) patients, 3.9–32.9 months after TIPS creation.ConclusionsTIPS creation may be effective and safe for the prevention of gastric variceal rebleeding in patients with HCC.