Plug-Assisted Retrograde Transvenous Obliteration (PARTO): Anatomical Factors Determining Procedure Outcome.

PURPOSE: To study various anatomical factors determining procedure success versus failure for plug-assisted retrograde transvenous obliteration (PARTO) of gastro-lieno-renal shunt. MATERIALS AND METHODS: A retrospective review of 50 patients (M:F-37:13; mean age 58.4yrs) who were planned for PARTO of gastro-lieno-renal shunt from July 2017 to July 2019 was done. Anatomical factors [shunt diameter, shunt angle, shunt orientation, left renal vein (LRV) size/calibre and distance of shunt from renal vein-IVC confluence] were analysed on a pre-procedure CT. Statistical analysis of the data was done to assess the relationship between these factors and technical success/failure. RESULTS: PARTO was successfully performed in 82% (n = 41). Analysis of anatomical factors showed that aneurysmal dilatation of the LRV, extreme acute/obtuse angulation and extreme antero-posterior orientation of the shunt in relation to the LRV was associated with higher probability of technical failure of PARTO. Minimum/maximum and entry point shunt diameter was not associated with procedure outcome. It was also noted that an increased distance of the shunt from the renal vein-IVC confluence favoured trans-jugular over trans-femoral venous access for PARTO. CONCLUSION: Knowledge of various anatomical factors of gastro-lieno-renal shunt may help in deciding the access route for PARTO and may determine technical success/failure. Alternate methods like BRTO or coil-assisted obliteration (CARTO) or anterograde obliteration of the shunt via trans-hepatic/splenic route might be needed in such circumstances.

Efficacy and safety of percutaneous microwave ablation for hepatocellular carcinomas <4 cm in difficult location.

OBJECTIVE: Tumor location is a critical factor for determining technical success and local recurrence following percutaneous ablation of hepatocellular carcinomas (HCC). The purpose of this retrospective study was to evaluate the safety and outcome measures of percutaneous microwave ablation (pMWA) for HCCs <4 cm in difficult locations. METHODS: Retrospective review included 81 patients who underwent pMWA for HCCs <4 cm. Fourty-three patients (30 males and 13 females; mean age, 61 years) with 53 HCCs located near the diaphragm, heart, gallbladder, kidney, gastrointestinal tract, large vessel and exophytic location were included under difficult location group. Thirty-eight patients (29 males and nine females; mean age, 60 years) with 48 HCCs in other locations were included under control group. Baseline demographics were recorded. Technical efficacy, local tumor progression (LTP), and complication rates were evaluated. RESULTS: Mean follow-up period was 3.4 months (range 1-7). There was no major complication in both the groups; two patients had a mild perihepatic hemorrhage in the difficult location group which was managed conservatively. There was no difference between the groups in the overall technical efficacy rate (84.9% vs 91.7%, p = 0.294), LTP rate (4.4% vs 2.2%. p = 0.57) or complication rate (4.6% vs 0%, p = 0.177). CONCLUSION: Our data suggest that there is no significant difference in technical efficacy, LTP or complication rates for MWA in both difficult and normal locations. ADVANCES IN KNOWLEDGE: With proper patient selection, pre-procedural planning and appropriate technique, pMWA is feasible, safe, and effective for small HCCs in difficult location with an acceptable range of complications.