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Effectiveness of different coils for endovascular coiling for intractable hepatic encephalopathy caused by a
Toru Ishikawa1, Michitaka Imai1, Saori Endo1
1Department of Gastroenterology, Saiseikai Niigata Hospital, Niigata, Japan.
Insights
Hydrogel-coated coils significantly reduce the number of coils needed for hepatic encephalopathy (HE) treatment via balloon-occluded retrograde transvenous obliteration (BRTO) or percutaneous transhepatic obliteration (PTO). Internal expansion hydrogel-coated coils are particularly effective for portosystemic shunt occlusion.
Area of Science:
- Interventional Radiology
- Vascular Surgery
- Hepatology
Background:
- Intractable hepatic encephalopathy (HE) is managed using interventional radiology techniques like balloon-occluded retrograde transvenous obliteration (BRTO) and percutaneous transhepatic obliteration (PTO).
- Optimal coil selection for endovascular coiling to prevent recanalization in BRTO and PTO procedures for HE remains unclear.
- This study addresses the lack of comparative data on coil types for these interventions.
Purpose of the Study:
- To compare the efficacy of different coil types (bare, fiber, hydrogel-coated) in endovascular coiling for BRTO and PTO in patients with intractable HE.
- To evaluate the number of coils required for complete portosystemic shunt occlusion using various coil types and expansion mechanisms.
- To identify the most effective coil type and expansion strategy for preventing recanalization.
Main Methods:
- Retrospective analysis of 38 patients undergoing BRTO or PTO for HE due to portosystemic shunts.
- Comparison of the mean number of bare, fiber, and hydrogel-coated coils needed for complete occlusion.
- Evaluation of different expansion types (external vs. internal) of hydrogel-coated coils.
Main Results:
- Hydrogel-coated coils required significantly fewer units (mean 10.70) for complete occlusion compared to bare (19.32) and fiber coils (18.11).
- No significant difference in portosystemic shunt size was observed across coil types.
- Internal expansion hydrogel-coated coils demonstrated high efficacy, requiring a mean of 8.5 coils for occlusion.
Conclusions:
- Hydrogel-coated coils are effective for endovascular coiling in treating HE caused by portosystemic shunts.
- Internal expansion hydrogel-coated coils show promise as a first-line option for achieving complete occlusion and preventing recanalization.
- Careful coil selection is crucial, as vessel expansion can impact occlusion efficacy.
Background:
Interventional radiology (IVR), including balloon-occluded retrograde transvenous obliteration (BRTO) and percutaneous transhepatic obliteration (PTO), is performed for patients with intractable hepatic encephalopathy (HE). However, information on the appropriate coil for endovascular coiling for preventing recanalization is lacking. This study aimed to compare the different types of coils for endovascular coiling used in BRTO and PTO for cases of intractable HE.
Methods:
This retrospective study included patients who underwent endovascular coiling with BRTO or PTO for HE caused by portosystemic shunts. The number of coils required for complete occlusion was compared among bare, fiber, and hydrogel-coated coils, and the expansion types that close the gap between and inside the hydrogel-coated coils were also compared.
Results:
Of 38 patients (age range, 30-86 years), 16 and 22 underwent BRTO and PTO, respectively, using bare (19 patients), fiber (8 patients), and hydrogel-coated coils (10 patients; external expansion type, 4; internal expansion type, 6). No significant differences in the size of portosystemic shunts were observed according to the type of coil. The mean number of coils required for complete occlusion varied (bare coils, 19.32; fiber coils, 18.11; hydrogel-coated coils, 10.70). Significantly fewer coils were required for endovascular coiling with hydrogel-coated coils. In the internal expansion type, a mean of 8.5 coils was required for occlusion.
Conclusions:
In some patients who underwent portal vein embolization, complete occlusion was not achieved with the scheduled type of coil because of slight expansion of blood vessels due to coil pressure. The findings suggested that hydrogel-coated coils were effective in endovascular coiling for HE caused by a portosystemic shunt, and internal expansion-type hydrogel-coated coils may be effective for the first-line procedure.
