Hepatobiliary Infection after Transjugular Intrahepatic Portosystemic Shunt Creation in Patients with Prior Biliary Intervention: A Multi-Institution Retrospective Study

PURPOSE

To estimate the risk of hepatobiliary infection, including endoTIPSitis, liver abscesses, and cholangitis, after transjugular intrahepatic portosystemic shunt (TIPS) creation in patients with prior biliary intervention.

MATERIALS AND METHODS

This multi-institution, retrospective study identified 76 patients (n = 48 males; mean age, 54.9 years; mean Model for End-stage Liver Disease [MELD] score, 13.2; n = 45 for ascites and n = 23 for varices; n = 31 with prior liver transplantation) among 2,130 (3.6%) undergoing TIPS creation who had prior biliary intervention (n = 19 bilioenteric anastomoses, n = 35 sphincterotomies, n = 28 internal plastic stent placements, n = 4 internal metal stent placements, and n = 6 percutaneous biliary drain placements). The baseline risk of post-TIPS creation hepatobiliary infection was estimated from a control group of 1,202 TIPS creation procedures in patients without prior biliary intervention.

RESULTS

Eleven (14.5%) of 76 patients developed hepatobiliary infection after TIPS creation, including 7 with endoTIPSitis, 4 with hepatic abscesses, and 2 with cholangitis. The 30-day risk of infection was 10.9% (95% confidence interval [CI], 3.5%-17.8%), significantly higher than the 0.4% risk (95% CI, 0.1%-0.8%) observed in patients without prior biliary intervention (hazard ratio [HR], 25.56; 95% CI, 8.36-78.13; P < .001). All types of biliary intervention were associated with increased risk of infection, with bilioenteric anastomoses conferring the highest risk. Paradoxically, among patients with prior biliary intervention, use of postprocedural antibiotic prophylaxis was associated with an increased infection risk (HR, 19.85; 95% CI, 2.44-161.50; P = .005). Microbial culture data showed high rates of Enterococcus, Klebsiella, and Candida species.

CONCLUSIONS

Prior biliary intervention was associated with a 10.9% risk of hepatobiliary infection, including endoTIPSitis, liver abscess, and cholangitis, within 30 days after TIPS creation.

Single-plant-omics reveals the cascade of transcriptional changes during the vegetative-to-reproductive transition

Plants undergo rapid developmental transitions, which occur contemporaneously with gradual changes in physiology. Moreover, individual plants within a population undergo developmental transitions asynchronously. Single-plant-omics has the potential to distinguish between transcriptional events that are associated with these binary and continuous processes. Furthermore, we can use single-plant-omics to order individual plants by their intrinsic biological age, providing a high-resolution transcriptional time series. We performed RNA-seq on leaves from a large population of wild-type Arabidopsis (Arabidopsis thaliana) during the vegetative-to-reproductive transition. Though most transcripts were differentially expressed between bolted and unbolted plants, some regulators were more closely associated with leaf size and biomass. Using a pseudotime inference algorithm, we determined that some senescence-associated processes, such as the reduction in ribosome biogenesis, were evident in the transcriptome before a bolt was visible. Even in this near-isogenic population, some variants are associated with developmental traits. These results support the use of single-plant-omics to uncover rapid transcriptional dynamics by exploiting developmental asynchrony.

Computed Tomography Volumetry of Bone Cement: Retrospective Blinded Validation of Commercially Available Semi-automated Edge Detection Software

OBJECTIVE

Cement volumes are increasingly linked to orthopedic oncology and neurosurgical outcomes (construct durability, adjacent fracture), but manual cement volumetry remains time prohibitive. The authors aim to report performance of PACS-integrated volumetric software specifically for barium-enhanced polymethylmethacrylate cement.

METHODS

Institutional review board-approved single-institution retrospective review of patients from 2019-2022 undergoing kyphoplasty for pathological compression fractures with a quantitative cement infuser providing true cement volume. An operator blinded to true cement volumes retrospectively performed software-assisted volumetry on follow-up computed tomography scans.

RESULTS

Included were 91 kyphoplasty levels in 56 patients: mean age, 62 years (range, 34-85 years), 73% female. True cement volume (available for 44 of 66 procedures) was mean 4.5 mL per level (range, 1.2-15.6 mL). Measured cement volume (available for all procedures) yielded a mean of 6.1 mL per level (range, 1.5-27.9 mL). For the 57 levels (39 patients) where both true and measured cement volumes were available, linear regression intercept and slope were 1.46 (95% CI = 0.97-1.95, P < 0.001) and 0.52 (CI = 0.47-0.57, P < 0.001), respectively, suggesting measured volume averaged 1.46 mL greater than true volume, with each additional milliliter of measured volume corresponding to approximately 0.52 mL of true volume. There was no significant difference in the relationship between estimated and actual cement volume in thoracic levels (intercept = -0.24, CI = -1.13 to 0.66, P = 0.61; slope = 0.03, CI = -0.14 to 0.19, P = 0.73) compared with lumbar levels. The goodness-of-fit of the regression model was strong ( R2 = 0.81). Discrepancies ranged from 90% underestimation to 52% overestimation; average, 17% overestimation.

CONCLUSIONS

Semi-automated volumetry maintained a strong correlation with true volumes across the thoracic and lumbar curvatures, overestimating cement volume by a mean of 17% or 1.46 mL.

Correlation of Ablation Volume with Renal Function Loss after Cryoablation in Solitary Functioning Kidneys

PURPOSE

To determine the degree of renal function deterioration after renal cryoablation in patients with a solitary functioning kidney on the basis of ablation volume.

MATERIALS AND METHODS

Over a 15-year period, 81 percutaneous cryoablations were performed in solitary functioning kidneys. After exclusion of patients with baseline end-stage renal disease (ESRD) and insufficient follow-up, analysis was performed on 65 procedures in 52 patients (40 men; mean age, 63.5 years). The postcryoablation renal function was based on the lowest serum creatinine within 6 months after procedure. Renal function change was defined as percentage glomerular filtration rate (GFR) change. Volumetric analysis was performed on the target lesion, renal parenchyma, and ablation zone.

RESULTS

The median tumor diameter was 2.0 cm (range, 0.8-4.7 cm). The median baseline GFR decreased from 56.4 mL/min/1.73 m2 (range, 17.5-89.7 mL/min/1.73 m2) to 46.9 mL/min/1.73 m2 (range, 16.5-89.7 mL/min/1.73 m2) at median of 95 days (P < .001), equating to a -7.9% median renal function change (range, -45.0% to +30.7%). All patients had Stage 2 or worse chronic kidney disease, and baseline function did not correlate with renal function change. The median volume of ablated parenchyma was 19.7 mL (range, 2.4-87.3 mL), equating to 8.1% (range, 0.7%-37.2%) of total parenchyma. The volume of parenchymal volume ablated correlated significantly with renal function loss, whereas age, hypertension, and diabetes mellitus did not. No patient developed ESRD within 1 year after cryoablation.

CONCLUSIONS

Cryoablation in solitary functioning kidneys resulted in a modest reduction in renal function, even in patients with chronic kidney disease and ablations up to 20% of renal parenchymal volume.

Increasing utilization of contrast-enhanced ultrasound during abdominal biopsies: impact of an educational training program

RATIONAL AND OBJECTIVES

To increase utilization of contrast-enhanced ultrasound (CEUS) during ultrasound-guided targeted liver biopsies.

MATERIAL AND METHODS

Two educational training interventions performed to increase use of CEUS. First, 14 radiologists (fellowship-trained in Abdominal Imaging) given didactic teaching and case presentations on the use of CEUS. Second, hands-on teaching on how to use CEUS provided to the same group. To determine the efficacy of these two interventions, radiologists completed anonymous surveys to determine the level of understanding and acceptability of using CEUS before and 6 months after CEUS training. In addition, the percentage of CEUS assisted liver biopsies was compared for the 6 months before and 6 months after the training.

RESULTS

Pre-training survey completed by 11 radiologists and post-training survey completed by 9 radiologists. Before training, 11% survey responders use CEUS routinely, whereas 89% never or rarely used it. After training, 54% of respondents were new users and 100% reported they planned to use CEUS in the future. Unfamiliarity (71%) was the main reason for not using it. After training, 25% reported lack of comfort with using CEUS as the main reason for not using CEUS. During six months before training, CEUS was administered in 6% (10/172) of targeted liver biopsies. Six months after training, CEUS was used nearly twice as often (10%, 16/160, P = 0.09, 1-sided Boschloo test). The number of radiologists using CEUS increased to 57% (8/14) after training compared to 20% (3/14, P = 0.03, 1-sided Boschloo) before training.

CONCLUSION

Educational training intervention increases use of CEUS during ultrasound-guided targeted liver biopsies.

Long term impact of transjugular intrahepatic portosystemic shunt (TIPS) creation on hepatic morphology

PURPOSE

The purpose of this study was to evaluate long-term morphologic changes occurring in the liver after TIPS creation with correlation with hepatic function to gain insight on the physiologic impact of TIPS on the liver.

METHODS

This retrospective study included patients who underwent TIPS creation between 2005 and 2022 and had contrasted CT or MRI studies prior to and between 1 and 2 years post procedure. Strict exclusion criteria were applied to avoid confounding. Parenchymal volume and vessel measurements were assessed on the pre- and post-TIPS CT or MRI and MELD scores calculated.

RESULTS

Of 580 patients undergoing TIPS creation, 65 patients (mean age, 55 years; 36 males) had pre-TIPS and post-TIPS imaging meeting inclusion criteria at median 16.5 months. After TIPS, the mean MELD score increased (12.9 to 15.4; p = 0.008) and total liver volume decreased (1730 to 1432 mL; p < 0.001). However, the magnitude of volume change did not correlate with MELD change. Neither portosystemic gradient nor TIPS laterality correlated with total or lobar hepatic volume changes or MELD changes. The main portal vein diameter increased (15.0 to 18.7 mm; p < 0.001). Thrombosis of the hepatic vein used for TIPS creation resulted in a mean increase in MELD of +4.1 compared to -2.1 in patients who had a patent and normal hepatic vein (p = 0.007).

CONCLUSIONS

Given lack of correlation between portosystemic gradient, hepatic atrophy, hepatic function, and TIPS laterality, the alterations in portal flow dynamics after TIPS may not be impactful to hepatic function. However, hepatic vein patency after TIPS correlated with improved hepatic function.

Complex epistatic interactions between ELF3, PRR9, and PRR7 regulate the circadian clock and plant physiology

Circadian clocks are endogenous timekeeping mechanisms that coordinate internal physiological responses with the external environment. EARLY FLOWERING3 (ELF3), PSEUDO RESPONSE REGULATOR (PRR9), and PRR7 are essential components of the plant circadian clock and facilitate entrainment of the clock to internal and external stimuli. Previous studies have highlighted a critical role for ELF3 in repressing the expression of PRR9 and PRR7. However, the functional significance of activity in regulating circadian clock dynamics and plant development is unknown. To explore this regulatory dynamic further, we first employed mathematical modeling to simulate the effect of the prr9/prr7 mutation on the elf3 circadian phenotype. These simulations suggested that simultaneous mutations in prr9/prr7 could rescue the elf3 circadian arrhythmia. Following these simulations, we generated all Arabidopsis elf3/prr9/prr7 mutant combinations and investigated their circadian and developmental phenotypes. Although these assays could not replicate the results from the mathematical modeling, our results have revealed a complex epistatic relationship between ELF3 and PRR9/7 in regulating different aspects of plant development. ELF3 was essential for hypocotyl development under ambient and warm temperatures, while PRR9 was critical for root thermomorphogenesis. Finally, mutations in prr9 and prr7 rescued the photoperiod-insensitive flowering phenotype of the elf3 mutant. Together, our results highlight the importance of investigating the genetic relationship among plant circadian genes.

Vortex-assisted resin y90 delivery via 175 cm Truselect microcatheter: case factors for high residual despite double-flush protocol

PURPOSE

To report efficiency of resin y90 delivery using SIROS via 175 cm TruSelect microcatheter with double-flush protocol (40 ml dextrose total).

METHODS

IRB-approved retrospective review of all patients undergoing SIROS injection of y90 Sir-Spheres via TruSelect from 2019 through 2022 at one quaternary-care academic institution, including medical records.

RESULTS

Included were 48 infusions in 25 patients across 11 cancer histologies. Mean planned, delivered, and residual activities were 28 ± 17, 27 ± 17, 1.1 ± 0.56 mCi respectively (mean residual 4.9% ± 2.8%) across flex-dosing precalibrations including 1-day, 2-day, and 3-day SIROS (4/51, 16/51, and 28/51). Mean liver treatment volume was 483 ± 306 ml with target dose mean of 128 ± 26 Gy in non-segmentectomy cases; Radiation segmentectomy was performed in 15/48 (31%). Arterial stasis was documented in 9/48 (19%) of cases. Use of a 3-day precalibrated SIROS dose, use of activity <10 mCi, treatment of smaller liver volumes (<200 ml) and documentation of stasis were associated with higher residual activity ( P  = 0.025, P  = 0.0007, P  = 0.0177, and P  = 0.049, respectively) were associated with higher residuals.

CONCLUSION

Combining the new technologies of SIROS and the Truselect microcatheter with a double-flush protocol yielded <10% residual in 94% of y90 infusions. Future studies may clarify if the predictors of high residual dose seen here may warrant microcatheter-specific considerations for dosimetry or dose preparation at the Radiopharmacy level.

Intravascular Ultrasound Guidance for Transjugular Intrahepatic Portosystemic Shunt Creation Reduces Laboratory Markers of Acute Liver Injury

PURPOSE

To compare the laboratory markers of acute liver injury after transjugular intrahepatic portosystemic shunt (TIPS) creation performed using intravascular ultrasound (IVUS) guidance with those using other techniques.

MATERIALS AND METHODS

This single-center, retrospective study examined 293 TIPS procedures performed between 2014 and 2022 (160 men; mean age, 57.4 years; 71.7% with ascites, 158 with IVUS). Laboratory changes on postprocedural day (PPD) 1 were classified based on Common Terminology Criteria for Adverse Events (CTCAE) grades and were compared between IVUS and non-IVUS cases.

RESULTS

IVUS cases had a lower baseline Model for End-Stage Liver Disease (MELD) score (12.5 vs 13.7, P = .016), higher pre- (16.8 vs 15.2, P = .009), and post-TIPS (6.6 vs 5.4 mm Hg, P < .001) pressure gradient, smaller stent diameter (9.2 vs 9.9 mm, P < .001), and fewer needle passes (2.4 vs 4.2, P < .001). IVUS predicted a lower PPD 1 CTCAE grade for aspartate transaminase (8.0% vs 22.2% grade ≥ 2, P = .010), alanine transaminase (ALT) (2.2% vs 7.1%, P = .017), and bilirubin (9.4% vs 26.2%, P < .001), findings confirmed using multivariable regression and propensity score analysis. IVUS predicted fewer adverse events (1.3% vs 8.1%, P = .008) and an increased likelihood of PPD 1 discharge (81% vs 59%, P = .004). IVUS was not associated with differences in PPD 30 MELD scores or 30-day survival; however, higher PPD 1 ALT (β = 1.96, P = .008) and bilirubin levels (β = 1.38, P = .004) predicted larger PPD 30 MELD score increase. Higher increases in ALT level predicted worse 30-day survival (hazard ratio, 1.93; P = .021).

CONCLUSION

IVUS resulted in less laboratory evidence of acute liver injury immediately following TIPS creation.

Phototropin phosphorylation of ROOT PHOTOTROPISM 2 and its role in mediating phototropism, leaf positioning, and chloroplast accumulation movement in Arabidopsis

Directional movements impact the ability of plants to respond and adjust their growth accordingly to the prevailing light environment. The plasma-membrane associated protein, ROOT PHOTOTROPISM 2 (RPT2) is a key signalling component involved in chloroplast accumulation movement, leaf positioning, and phototropism, all of which are regulated redundantly by the ultraviolet/blue light-activated AGC kinases phototropin 1 and 2 (phot1 and phot2). We recently demonstrated that members of the NON-PHOTOTROPIC HYPOCOTYL 3 (NPH3)/RPT2-like (NRL) family in Arabidopsis thaliana, including RPT2, are directly phosphorylated by phot1. However, whether RPT2 is a substrate for phot2, and the biological significance of phot phosphorylation of RPT2 remains to be determined. Here, we show that RPT2 is phosphorylated by both phot1 and phot2 at a conserved serine residue (S591) within the C-terminal region of the protein. Blue light triggered the association of 14-3-3 proteins with RPT2 consistent with S591 acting as a 14-3-3 binding site. Mutation of S591 had no effect on the plasma membrane localization of RPT2 but reduced its functionality for leaf positioning and phototropism. Moreover, our findings indicate that S591 phosphorylation within the C-terminus of RPT2 is required for chloroplast accumulation movement to low level blue light. Taken together, these findings further highlight the importance of the C-terminal region of NRL proteins and how its phosphorylation contributes to phot receptor signalling in plants.

Intravascular Ultrasound-Guided Transvenous Biopsy of Retroperitoneal Lymph Nodes: Diagnostic Accuracy and Safety Compared with CT-Guided Percutaneous Biopsy

PURPOSE

To compare the diagnostic accuracy and adverse event rates of intravascular ultrasound (US)-guided transvenous biopsy (TVB) versus those of computed tomography (CT)-guided percutaneous needle biopsy (PNB) for retroperitoneal (RP) lymph nodes.

MATERIALS AND METHODS

In this single-institution, retrospective study, 32 intravascular US-guided TVB procedures and a sample of 34 CT-guided PNB procedures for RP lymph nodes where targets were deemed amenable to intravascular US-guided TVB were analyzed. Procedural metrics, including diagnostic accuracy, defined as diagnostic of malignancy or a clinically verifiable benign result, and adverse event rates were compared.

RESULTS

The targets of intravascular US-guided TVB were primarily aortocaval (47%, 15/32) or precaval (34%, 11/32), whereas those of CT-guided PNB were primarily right pericaval (44%, 15/34) or retrocaval (44%, 15/34) (P < .001). The targets of intravascular US-guided TVB averaged 2.4 cm in the long axis (range, 1.3-3.7 cm) compared with 2.9 cm (range, 1.4-5.7 cm) for those of CT-guided PNB (P = .02). There was no difference in the average number of needle passes (3.8 for intravascular US-guided TVB vs 3.9 for CT-guided PNB; P = .68). The diagnostic accuracy was 94% (30/32) and the adverse event rate was 3.1% (1/32) for intravascular US-guided TVB, similar to those of CT-guided PNB (accuracy, 91% [31/34]; adverse event rate, 2.9% [1/34]).

CONCLUSIONS

Intravascular US-guided TVB had a diagnostic accuracy and adverse event rate similar to CT-guided PNB for RP lymph nodes, indicating that intravascular US-guided TVB may be as safe and effective as conventional biopsy approaches for appropriately selected targets.

Coaxial Stent Graft inside a Constraining Stent for Transjugular Intrahepatic Portosystemic Shunt Reduction

A technique to create a coaxial, self-expanding stent graft inside a constraining, bare-metal, balloon-expandable stent for transjugular intrahepatic portosystemic shunt (TIPS) reduction is described. The key steps are performed on a back table rather than inside the patient, and the resulting construct is deployed using standard unsheathing maneuvers. The construct was used in 4 patients to make 6 TIPS diameter reductions (mean postreduction diameter, 6 mm; range, 0-8 mm), all resulting in increases in the portosystemic pressure gradient (mean increase, 6 mm Hg; range, 1-19 mm Hg). On average, hepatic encephalopathy improved 1 point on the West Haven scale (range, 0-2).