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Yuan-Cheng Chiang

Publications and source records attributed to Yuan-Cheng Chiang.

8 recordsLinked to original sources
PubMed2006

Anatomical and technical aspects of hepatic artery reconstruction in living donor liver transplantation.

BACKGROUND: We describe our experience with arterial reconstruction in living donor liver transplantation (LDLT) focusing on anatomic and technical aspects. METHODS: From June 1994 to February 2003, 132 grafts were implanted in 130 LDLT recipients including 1 re-transplant and 1 dual graft transplantation. Donor and recipient records were retrospectively reviewed. Anatomical variations in graft arteries were classified as: Type I, single pedicle with (Ia) or without (Ib) aberrant artery (left hepatic artery (HA) from left gastric artery or right HA from superior mesenteric artery); Type II, double pedicles with (IIa) or without (IIb) aberrant artery; Type III, equal to or greater than 3 pedicles. Statistical analyses were carried out using Mann-Whitney U-test. RESULTS: There were 72 male and 58 female recipients. The median age at transplantation was 3 years (range, 0.5 to 61). In left grafts, there were 34 Type Ia, 6 Type Ib, 33 Type IIa, 13 Type IIb, and 3 Type III; whereas in right grafts, there were 35 Type Ia, 6 Type Ib, 1 Type IIa, and 1 Type IIb. Two-in-one (2-in-1) segmental resection technique in graft HA harvest was carried out whenever there were tiny arteries supplying the donor graft. All HA reconstructions were done under microvascular techniques. There was no donor mortality and 1 recipient in-hospital mortality. There was no graft or patient loss due to HA occlusion. Donor complications included 3 biloma, 1 bile leak, 1 biliary stricture, and 1 late intestinal obstruction secondary to postoperative adhesions that were all successfully managed by non-operative interventions, except the biliary stricture that needed a revision to Roux-en-Y hepatico-jejunostomy. The 1-year and 5-year recipient survivals were 98% and 94%, respectively. CONCLUSIONS: Successful HA reconstruction can be safely carried out in LDLT recipients and live donors with multiple graft arteries using the 2-in-1 segmental resection of donor HA under microvascular techniques.

Adolescent↗
PubMed2006

Thin anterolateral thigh perforator flap using a modified perforator microdissection technique and its clinical application for foot resurfacing.

BACKGROUND: A thin skin flap is often required for optimal resurfacing of particular areas of the body. An anterolateral thigh perforator flap can be thinned to an extent to which it is vascularized by the subdermal plexus only. This study presents a novel flap thinning technique and its application for resurfacing the dorsum of the foot. METHODS: From July of 2002 to October of 2003, 18 patients underwent resurfacing of the dorsum of the foot with thin anterolateral thigh flaps. The main perforators were strategically located in the flap center to keep the peripheral area within the vascular territory. The flaps were larger than needed, initially elevated subfascially, and then thinned to the suitable thickness while the pedicle was still attached. The dissection of perforators in the adipose layer close to the dermis entry was carried out microscopically. Flap sizes ranged from 3 x 3 to 16 x 8 cm. RESULTS: Seventeen flaps survived completely and one had distal superficial necrosis of 1 x 2 cm. No debulking procedures were necessary. Average follow-up was 12 months. CONCLUSIONS: A thin flap vascularized through subdermal plexus is reliable. Microsurgical dissection of the perforator is a recommended technique. The thin anterolateral thigh perforator flap provides ideal reconstruction in resurfacing the dorsum of the foot.

Adolescent↗
PubMed2005

Double free flaps in head and neck reconstruction.

This article discusses the indications for and the advantages and principles of flap combinations and the selection of two pairs of recipient vessels for double free-flap transfers in reconstruction of extensive composite head and neck defects.

Fibula↗
PubMed2005

Deceased-donor liver transplantation: 10 years' experience at Change Gung Memorial Hospital-Kaohsiung Medical Center.

BACKGROUND: The purpose of this study was to summarize the outcomes we achieved using deceased-donor liver transplantation (DDLT) in the past 10 years at Chang Gung Memorial Hospital-Kaohsiung Medical Center (CGMH-KMC). METHODS: Between March 1993 and March 2003, 53 DDLTs were performed at CGMH-KMC. Patients were divided into 2 stages: stage 1 (n = 22) from March 1993 to February 1998, and stage 2 (n = 31) from March 1998 to March 2003. Indications for transplantation, patient demographics, surgical procedures, and long-term outcomes were reviewed. RESULTS: Indications for transplantation were biliary atresia (16), post-hepatitis B/C viral cirrhosis with or without hepatocellular carcinoma (21), Wilson's disease (8), primary biliary cirrhosis (3), and miscellaneous (5). Two retransplants were carried out for secondary biliary cirrhosis using primary live-donor liver transplantation (LDLT). Ten patients received grafts from 6 split-liver transplantations. Over-all Kaplan-Meier 1-, 3-, and 5-year survival rates were 88.46%, 83.86%, and 79.87%, respectively. A significant improvement in patient survival was observed in stage 2. The Kaplan-Meier 1- and 5-year patient survival rates in stage 2 were 96.67% and 92.95%, respectively. Fifteen patients developed vascular complications. Nine patients died in this series for an overall mortality rate of 17%. CONCLUSIONS: Deceased-donor liver transplantation is well established as the treatment of choice for acute and chronic liver failure in Taiwan. Satisfactory outcomes have been attained in those transplanted to date.

Adolescent↗
PubMed2004

Fingertip replantation using the subdermal pocket procedure.

Restoration of finger length and function are the goals of replantation after fingertip amputation. Methods include microsurgical replantation and nonmicrosurgical replantation, such as composite graft techniques. To increase the survival rates for composite grafts, the subcutaneous pocket procedure has been used as a salvage procedure. The subdermal pocket procedure, which is a modification of the subcutaneous pocket procedure, was used for replantation of 17 fingertips in 16 consecutive patients. Eight fingertips experienced guillotine injuries and the other nine fingertips experienced crush injuries. Revascularization of one digital artery without available venous outflow was performed for six fingers, and composite graft techniques were used for the other 11 fingers. The success rate was 16 of 17 cases. The difference in success rates for guillotine versus crush injuries was statistically significant. Comparison of patients with arterial anastomoses and patients without arterial anastomoses also indicated a statistically significant difference. Thirteen fingertips survived completely. One finger, demonstrating complete loss and early termination of the pocketing procedure, was amputated on the eighth postoperative day. Two fingers were partially lost because of severe crushing injuries. One finger demonstrated partial loss of more than one quarter of the fingertip, which required secondary revision, because the patient was a heavy smoker. The pocketing period was 8 +/- 1 days (mean +/- SD, n = 6) for the fingers revascularized with one digital arterial anastomosis and 13.3 +/- 1.9 days (n = 10) for the fingers successfully replanted with composite graft techniques. The mean active range of motion of the interphalangeal joint of the three thumbs was 65 +/- 5 degrees, and that of the distal interphalangeal joint of the other 11 fingers was 51 +/- 11 degrees. The static two-point discrimination result was 6.4 +/- 1.0 mm (n = 14) after an average of 11 +/- 5 months of follow-up monitoring. Compared with other methods, the subdermal pocket procedure has the advantages of exact subdermal/subdermal contact, a shorter pocketing period, and more feasible observation. The method can offer an alternative salvage procedure for fingertip amputations with no suitable vessels available for microsurgical replantation.

Adolescent↗
PubMed2003

Ionized calcium changes during living-donor liver transplantation in patients with and without administration of blood-bank products.

Exogenous citrate load from blood transfusion during orthotopic liver transplantation is thought to be the main cause of ionized hypocalcemia, which may result in hemodynamic instability. This implies that if no blood is transfused, chelation of free ionized calcium (Ca(++)) by citrate is avoided and supplemental calcium need not be given. For this study, we divided 39 pediatric living-donor liver transplant patients into two groups according to the blood component replacement given: group I received packed red blood cells and fresh frozen plasma with and without 5% albumin, and group II received 5% albumin alone. The intra-operative serial ionized calcium level was recorded, and the amount of calcium chloride replacement to maintain acceptable blood Ca(++) levels was compared between the groups. The mean serum ionized calcium level changes of both groups could be maintained within lower-to-normal limits intra-operatively. The amount of supplemental calcium chloride required to correct the hypo-ionized calcium was not significantly different between the groups. We can conclude that if an exogenous citrate load is eliminated by the avoidance of blood transfusion and 5% albumin infusion is used, instead, to replace the blood and ascites loss during OLT, the risk of ionic hypocalcemia still persists. Serum Ca(++) monitoring and adequate replacement are, therefore, still required in this setting.

Adult↗
PubMedDate not supplied

Porcine heterotopic composite tissue allograft transplantation using a large animal model for preclinical studies.

BACKGROUND: Composite tissue allograft (CTA) transplantation is currently limited by the risks of side effects resulting from long-term high-dose immunosuppression. Therefore, preclinical animal models are essential to help CTA transplantation advance into clinical reality. Evidence has shown that small-animal model (rodents) immunotherapy protocols cannot be directly applied to humans. This study investigated whether a miniature porcine model is reproducible for preclinical studies. METHODS: Based on the concept of vascularized skeletal tissue allograft transplantation, limb heterotopic allograft tissue from a mismatched donor miniature pig consisting of the distal femur, knee joint, tibia, fibula, and surrounding muscle with a vascularized skin paddle model supplied by the superficial femoral vessels was transplanted into recipient pigs. Swine viability and rejection signs of the allograft were monitored postoperatively. Histopathological changes in the allograft tissues were examined using hematoxylin and eosin staining if the allo-skin flap was rejected. RESULTS: The recipient pigs were ambulatory immediately following surgery. The flaps showed no visible signs of rejection over the first 4 days of observation. The skin flaps appeared bluish-purple and edematous on postoperative days 5 approximately 7, and progressed to tissue necrosis and rejection on postoperative days 8 approximately 13. Histological examination revealed marked mononuclear cell infiltration and necrotic changes in the all rejected tissues, especial in the allograft skin tissues (skin > muscle > bone > cartilage). CONCLUSIONS: The results showed this the porcine CTA model is reproducible and suitable for preclinical training for human CTA transplantation. Monitoring of the allo-skin flap is a useful strategy to evaluate composite tissue allograft rejection.

Animals↗