K. Sung

Early posttransplant hepatic venous outflow obstruction: Long‐term efficacy of primary stent placement

Although balloon angioplasty has been accepted as the safe and effective initial treatment to manage hepatic venous outflow abnormalities, it may induce rupture of the fresh anastomosis but also may be ineffective to eliminate various etiologies of venous outflow abnormalities in the early post‐transplant period. Therefore, we performed primary stent placement in 108 patients to treat early‐onset (≤4 weeks) post‐transplant hepatic venous outflow abnormality. The following parameters were documented retrospectively: technical success and complications: clinical success; recurrence; and patency of stent‐inserted hepatic veins.

Hepatic venous congestion in living donor liver transplantation: Preoperative quantitative prediction and follow‐up using computed tomography

Hepatic venous congestion (HVC) has not been assessed quantitatively prior to hepatectomy and its resolving mechanism has not been fully analyzed. We devised and verified a new method to predict HVC, in which HVC was estimated from delineation of middle hepatic vein (MHV) tributaries in computed tomography (CT) images. The predicted HVC was transferred to the right hepatic lobes of 20 living donors using a paper scale, and it was compared with the actual observed HVC that occurred after parenchymal transection and arterial clamping. The evolution of HVC from its emergence to resolution was followed up with CT. Volume proportions of the predicted and observed HVC were 31.7 ± 6.3% and 31.3 ± 9.4% of right lobe volume (RLV) (P = .74), respectively, which resulted in a prediction error of 3.8 ± 3.7% of RLV. We observed the changes in the HVC area of the right lobes both in donors without MHV trunk and in recipients with MHV reconstruction. After 7 days, the HVC of 33.5 ± 7.7% of RLV was changed to a computed tomography attenuation abnormality (CTAA) of 28.4 ± 5.3% of RLV in 12 donor remnant right lobes, and the HVC of 29.1 ± 11.5% of RLV was reduced to a CTAA of 9.3 ± 3.2% of RLV in 7 recipient right lobe grafts with MHV reconstruction. There was no parenchymal regeneration of the HVC area in donor remnant livers during first 7 days. In conclusion, we believe that this CT‐based method for HVC prediction deserves to be applied as an inevitable part of preoperative donor evaluation. The changes in CTAA observed in the right lobes of donors and recipients indicate that MHV reconstruction can effectively decrease the HVC area. (Liver Transpl 2004;10:763–770.)

Donor selection for procurement of right posterior segment graft in living donor liver transplantation

The right posterior segment (RPS) graft was introduced to overcome graft‐size mismatch when the donor liver demonstrates a disproportionately small left lobe (LL). As variants of liver anatomy seemed to be related to the feasibility of RPS graft procurement, in 2003, we performed a prospective study to assess its feasibility in 197 consecutive living donors. Variants of the portal vein (PV) were classified as type I (bifurcation), II (trifurcation), and III (independent RPS PV branching from main PV). The right hepatic artery, vein, and bile duct were also classified according to their branching pattern and location. PV variations were type I in 157 (79.7%) donors, type II in 15 (7.6%) donors, and type III in 25 (12.7%) donors. Mean volume proportion of LL plus caudate lobe was 35.3 ± 3.8% (range 24–4) of the whole liver volume (WLV). On exclusion of donors with LL greater than 35% of WLV, there were 14 (7.1%) donors revealing RPS greater than LL by over 3% of WLV. Of these 14 donors, 3 had type I PV with artery or bile duct anatomy not suitable for RPS procurement. One donor with type II PV and 9 out of 10 donors with type III PV met the anatomical conditions for RPS graft procurement. With the exclusion of caudate lobe volume, LL volume became less than 30% of WLV in all of these 14 donors. We successfully procured 3 RPS grafts, all with type III PV, out of 197 consecutive living donors. In conclusion, successful RPS graft procurement is highly possible, only when LL is disproportionately small (<30% of WLV) and the PV variant is type III. (Liver Transpl 2004;10:1150–1155.)

Percutaneous transhepatic cholangioscopic treatment of patients with benign bilio-enteric anastomotic strictures

BACKGROUNDnPercutaneous transhepatic cholangioscopy is a nonoperative method for accessing bilio-enteric anastomotic strictures that cannot be reached via the transpapillary route. This study evaluated the immediate and long-term results of treatment via percutaneous transhepatic cholangioscopy of patients with benign bilio-enteric anastomotic strictures.nnnMETHODSnA retrospective analysis was conducted of 21 patients who, between October 1994 and March 2001, had undergone percutaneous transhepatic cholangioscopy for bilio-enteric anastomotic strictures. Follow-up ranged from 12 to 79 months (mean 33.3 months).nnnRESULTSnThe initial technical success rate was 100%, and the short-term morbidity and mortality rates were, respectively, 14.3% and 0%. However, strictures recurred in 8 patients (38.1%) at a mean of 17.1 months (range 2-38 months). The success rate exclusive of patients with recurrent strictures was 61.9%, and the overall success rate was 81.0% when the procedures were repeated. The long-term morbidity rate was 38.1%, but most complications resolved with conservative treatment. In 17 patients (81.0%), strictures were complicated by biliary stones, and these were successfully treated via percutaneous transhepatic cholangioscopy (stone removal rate 94.1%, recurrence rate 37.5%).nnnCONCLUSIONSnPercutaneous transhepatic cholangioscopy-based treatment of patients with benign bilio-enteric anastomotic strictures is safe and effective. This minimally invasive method frequently can be used as a substitute for surgery.

Percutaneous transhepatic treatment of hepaticojejunal anastomotic biliary strictures after living donor liver transplantation

Endoscopic treatment has largely replaced surgery as the initial treatment for biliary strictures following living donor liver transplantation; however, this treatment is nearly impossible in patients who have previously undergone hepaticojejunostomy (HJ). We therefore retrospectively evaluated the efficacy of percutaneous transhepatic treatment in patients who developed HJ strictures following living donor liver transplantation. Percutaneous transhepatic biliary drainage and subsequent balloon dilation of biliary strictures were performed on 83 patients. Serial exchanges of drainage tubes with larger diameters up to 14 Fr were performed at 4‐week intervals. Drainage tubes were removed if follow‐up cholangiography revealed fluent passage of the contrast medium without recurrence of symptoms or changes in the biochemical findings. The clinical outcome, tube independence rate, and patency rate following drainage tube removal were retrospectively evaluated. Except for 2 patients who had failed negotiation of biliary strictures, clinical success was achieved in all 81 patients following percutaneous transhepatic treatment, and the drainage tubes were removed from 76 (93.8%) of these 81 patients. Tubes were removed 11.2 ± 7.4 months after initial percutaneous transhepatic biliary drainage. The recurrence rate at a mean of 36.0 ± 26.2 months following drainage tube removal was 15.8%. One‐ and three‐year primary patency rates were 95.3% ± 2.7% and 80.9% ± 5.2%, respectively. In conclusion, percutaneous transhepatic treatment is an effective alternative treatment for HJ strictures following living donor liver transplantation. However, further research will be required in order to minimize the duration of treatment and the stricture recurrence rate following tube removal. Liver Transpl 14:1323–1332, 2008.

Removal of retrievable self-expandable urethral stents: experience in 58 stents

The purpose of this study was to retrospectively evaluate the safety and efficacy of removing retrievable self-expandable urethral stents using a retrieval hook wire. Under fluoroscopic guidance, the removal of 58 polyurethane or PTFE (polytetrafluoroethylene)-covered stents was attempted in 33 patients using a retrieval hook wire. Indications for removal were elective removal (n=21), stent migration (n=19), formation of tissue hyperplasia around or inside of the stent (n=14), stent deformity (n=3), and severe pain (n=1). The mean time the stents remained in place was 64.8±42.9 days (range, 1–177 days). Fifty-six (97%) of the 58 stents were successfully removed using the retrieval hook wire despite the following difficulties; hook wire disconnection (n=2), untied drawstrings (n=3), and polyurethane membrane disruption/separation (n=4). The removal procedure using a retrieval hook wire failed in two stents (3%) which had migrated into the urinary bladder. One of the two stents with migration into the urinary bladder was removed using a snare through the cystostomy route. The overall complication rate was 14% (seven hematuria cases and one urethral tear case), and all were minor and spontaneously resolved without further treatment. In conclusion, removal of retrievable urethral stents using a retrieval hook wire was safe and effective despite some technical difficulties. It is a useful method for allowing temporary stent placement and solving various complications of stent use.