Lymphangiography and lymphatic embolisation for the treatment of chyle leaks after neck surgery: assessment of lymphangiography findings and embolisation techniques.

OBJECTIVE: To assess lymphangiography findings and outcome of lymphatic embolisation to manage chyle leak after neck surgery. METHODS: Consecutive cases of lymphangiography performed between April 2018 and May 2022 for management of chyle leaks related to neck surgery were retrospectively reviewed. Lymphangiography findings, techniques, and outcomes were analysed. RESULTS: Eight patients (mean age: 46.5 years) were included. Six patients had undergone radical neck dissection for thyroid cancer, and two had undergone lymph node excision. Clinical presentations were: chyle drainage through Jackson Pratt catheters in five patients, lymphorrhea through surgical wounds in two, and enlarging lymphocele in one. Lymphangiography techniques included: inguinal lymphangiography in four patients, retrograde lymphangiography in three, and transcervical lymphangiography in one. Lymphangiography revealed leaks in the terminal thoracic duct in two patients, bronchomediastinal trunk in two, jugular trunk in three, and superficial neck channels in one. Embolisation techniques included: non-selective embolisation of terminal thoracic duct (n = 2), selective embolisation of the jugular trunk (n = 3), selective embolisation of the bronchomediastinal trunk (n = 2), and intranodal glue embolisation of superficial neck channels (n = 1). One patient underwent a repeat procedure. Chyle leak resolved in all patients over a mean of 4.6 days. No complication was encountered. CONCLUSION: Lymphatic embolisation seems to be effective and safe in managing chyle leaks after neck surgery. Lymphangiography allowed for the categorisation of chyle leaks according to their location. Post-embolisation patency of the thoracic duct may be preserved in chyle leaks that do not directly involve the thoracic duct. ADVANCES IN KNOWLEDGE: Lymphatic embolisation is safe and effective in managing chyle leaks after neck surgery. On lymphangiography, the location of contrast media extravasation may not be consistent. The technique for embolisation should be based on the location of the leak. Post-embolisation patency of the thoracic duct may be preserved in chyle leaks that do not directly involve the thoracic duct.

Bare-Metal Stent in Dysfunctional Hemodialysis Access: An Assessment of Circuit Patency according to Access Type and Stent Location.

Purpose: To evaluate the circuit patency after nitinol bare-metal stent (BMS) placement according to the type of access and location of the stent in dysfunctional hemodialysis access. Materials and Methods: Between January 2017 and December 2019, 159 patients (mean age, 64.1 ± 13.2 years) underwent nitinol BMS placement for dysfunctional access. The location of stents was as follows: 18 brachiocephalic vein, 51 cephalic arch, 40 upper arm vein, 10 juxta-anastomotic vein, 7 arteriovenous (AV) anastomosis, and 33 graft-vein (GV) anastomosis. Circuit patency was evaluated by the Kaplan-Meier method, and cox regression model. Results: A total of 159 stents were successfully deployed in 103 AV fistula (AVF) and 56 AV graft (AVG). AVG showed lower primary and secondary patency at 12-months compared with AVF (primary patency; 25.0% vs. 44.7%; p = 0.005, secondary patency; 76.8% vs. 92.2%; p = 0.014). Cox regression model demonstrated poorer primary patency at 12 months after stenting in the cephalic arch and GV anastomosis compared with the other sites. Conclusion: AVF showed better primary and secondary circuit patency at 12 months following the placement of BMS compared with AVG. Stents in the cephalic arch and GV anastomosis were associated with poorer primary patency at 12 months compared to those in other locations.

Quantitative Assessment of the Portal Pressure for the Liver Surgery Using Serological Tests.

OBJECTIVE: To establish a reliable equation to predict hepatic venous pressure gradient (HVPG) using serological tests for surgical patients with hepatocellular carcinoma (HCC). BACKGROUND: Accurate assessment of portal pressure for surgical patients with HCC is important for safe hepatic resection (HR). The HVPG is regarded as the most reliable method to detect portal hypertension. However, HVPG is not utilized in many medical centers due to invasiveness of procedure. METHODS: Between 2006 and 2008, 171 patients (Correlation cohort), who underwent liver surgery in a tertiary hospital, were enrolled. Preoperative measurements of the HVPG and serological tests were performed simultaneously. Correlation between the HVPG and serological tests were analyzed to establish an equation for calculated HVPG (cHVPG). Between 2008 and 2013, 510 surgical patients (Application cohort) were evaluated, and HR recommended when cHVPG < 10 mm Hg. The outcomes of HR were analyzed to evaluate reliability of the cHVPG for HR. RESULTS: In the correlation cohort, the equation for cHVPG was established using multivariate linear regression analysis; cHVPG (mm Hg) = 0.209 × [ICG-R15 (%)] - 1.646 × [albumin (g/dL)] - 0.01×[platelet count (10)] + 1.669 × [PT-INR] + 8.911. In the application cohort, 425 patients with cHVPG < 10 mm Hg underwent HR. Among them, 357 had favorable value of ICG-R15 < 20% (group A), and 68 had unfavorable value of ICG-R15 ≥ 20% (group B). There was no significant difference in patient demographics, tumor characteristics, operative outcome, and survival rates between group A and B. CONCLUSIONS: The equation for cHVPG of this study was established on statistical reliability. The cHVPG could be useful to predict portal pressure quantitatively for surgical patients with HCC using serological tests.