Biomedical subjects

Ming-Huei Cheng

Publications and source records attributed to Ming-Huei Cheng.

34 records · Page 2Linked to original sources

PubMed2005

Selection of recipient vessels in double free-flap reconstruction of composite head and neck defects.

BACKGROUND: Massive defects of the head and neck regions after resection of advanced carcinoma often require two flaps for optimal reconstruction. This study focuses on the selection of proper recipient vessels. METHODS: A total of 262 free-flap transfers were performed in 130 patients using the two-flap approach (one patient received two flaps twice). RESULTS: For microvascular anastomosis of inner flaps (intraoral lining-bone reconstruction flaps), the ipsilateral facial artery was used in 56 flaps (42.8 percent), the ipsilateral superior thyroid artery was used in 49 flaps (37.4 percent), and a branch of the internal jugular vein was used as recipient vein in 101 flaps (77.1 percent). For external flaps (soft-tissue-external skin reconstruction flaps), the ipsilateral superior thyroid artery was used in 59 flaps (50.4 percent) and the transverse cervical artery was used in 19 flaps (16.2 percent). In 14 patients the inner flaps provided distal run-off for external flap revascularization. Only seven flaps required vein grafts; they were all used for external face reconstruction (2.8 percent). There were six total (2.3 percent) and 12 partial (4.6 percent) flap failures. CONCLUSIONS: Recipient vessel selection and preparation in primary head and neck cancer reconstruction requiring two simultaneous flaps should take into consideration (1) avoidance of unnecessary destruction during tumor ablations and preservation of as many neck vessels as possible, (2) length and diameter match between flap pedicles and recipient vessels to avoid vein grafts, and (3) possible need of another free-flap reconstruction for flap failure, complication, recurrence, or secondary primary cancers. The previously radiated or operated neck does not preclude the use of recipient vessels from that side. Distal run-off of the inner flap for external flap revascularization should be avoided if possible. Once those principles are observed, two-flap reconstruction for primary cancer presents no more difficulties than single-flap reconstruction.

Adult↗

PubMed2005

Deep inferior epigastric perforator flap for successful simultaneous breast and chest wall reconstruction in a Poland anomaly patient.

Breast reconstruction in female Poland anomaly remains a surgical challenge with variable chest wall deformity and nipple position. Pedicled latissimus dorsi myocutaneous flap with implant reconstruction may have several drawbacks and complications. Free deep inferior epigastric flap (DIEP) flap is a reliable option for postmastectomy breast reconstruction, but rarely reported in Poland anomaly. We presented a 52-year-old Poland anomaly patient who underwent successful reconstruction for breast and chest wall deformity using DIEP flap. Preoperative ultrasound Doppler study for internal mammary vessels is recommended for microsurgical anastomosis. Care should be taken with regard to the flap inset and the location of the nipple areolar complex.

Abdominal Muscles↗

PubMed2005

Microvascular free tissue transfer for treatment of osteoradionecrosis of the maxilla.

Head and neck tumors often require radiotherapy as part of the treatment protocol. Although it improves the survival rate in cancer patients, it may cause osteoradionecrosis, especially in the mandible and maxilla. Twelve patients with osteoradionecrosis of the maxilla were treated with microsurgical free tissue transplantations between April of 1996 and August of 2002. There were 10 male and two female patients, with a mean age of 60.2 years. The mean radiotherapy dose was 6674 cGy. The radiation dose could not be traced in three patients because radiotherapy was performed elsewhere. Radical sequestrectomy, soft-tissue debridement, and pathologic proof of no tumor recurrence were performed before microsurgical reconstruction. Free flaps used included the following: anterolateral thigh (n = 7), radial forearm (n = 2), rectus femoris musculocutaneous (n = 2), and supracondylar chimeric (n = 1) flaps. All flaps survived completely and reconstruction succeeded. During a mean 25-month follow-up period, ectropion, plate exposure, and mild infection were encountered in three patients and treated successfully. Radical debridement and obliteration of dead space with well-vascularized tissue are essential for successful treatment of maxillary osteoradionecrosis. The anterolateral thigh flap is most versatile for almost all types of soft-tissue defect reconstruction in the head and neck region.

Adult↗

PubMed2005

Intractable hiccups as an unusual presentation of a uterine leiomyoma: a case report.

BACKGROUND: Hiccups, or singultus, are an abrupt, intense contraction of the inspiratory muscles accompanied by closure of the glottis and are experienced by most people. people. CASE: A 41-year-old woman with a large uterine myoma presented with recurrent and intractable hiccup boutsfor 1 year. The hiccups resolved spontaneously after hysterectomy. CONCLUSION: A uterine leiomyoma, especially the subserosal type, might become a possible etiology of hiccups when large enough to cause irritation of the vagus or phrenic nerve.

Adult↗

PubMed2004

Strategies for a successful corrective Asian blepharoplasty after previously failed revisions.

Asian blepharoplasty, although a common procedure, has a relatively high rate of complications. Subtle imperfections and more serious iatrogenic complications often require immediate attention by the aesthetic surgeon. After attempted correction of the deformities, residual problems or new ones can arise. Blepharoptosis, supratarsal depression, an excessively high or low crease, a short or discontinuous crease, multiple creases, and asymmetric creases are the most commonly encountered complications that require special attention in this group, which has already undergone more than one surgical procedure. Between January of 1996 and December of 2002, 168 Asian blepharoplasty revisions were performed by one surgeon (S. H.-T. Chen); of these, 36 patients (21 percent) had previously undergone failed revisions. This subgroup of patients consisted of six with blepharoptosis, six with asymmetrical eyelid creases, three with supratarsal depressions, three with high creases, two with short creases, and 16 with combinations of these deformities. The results were graded as excellent, good, fair, or poor, based on the symmetry of the eyelids, palpebral fissures, crease heights, lengths, shapes, eyelid fullness, and overall aesthetics of the final outcome. A survey was performed of patient and surgeon satisfaction and factored into the grading system. With an average follow-up period of 16 months (6 to 60 months), 22 patients (61 percent) were found to have excellent results, 10 (28 percent) had good results, two (5.6 percent) had fair results, and two (5.6 percent) had poor results. Corrective procedures after failed revision Asian blepharoplasty require special strategic considerations because of the presence of extensive scarring and inadequate skin, muscle, and preaponeurotic fat and because of the occasional presence of dehiscence of the levator aponeurosis. By using careful preoperative evaluation, accurate measurements, precise preoperative planning, intraoperative fat repositioning or grafting, skin excision or redraping, and proper placement of anchoring sutures, successful outcomes can be achieved. The authors evaluate the outcomes and detail the surgical procedures that were used to achieve successful outcomes in this particularly challenging group of patients.

Asian People↗

PubMed2004

Breast reconstruction with a muscle-sparing free transverse rectus abdominis myocutaneous flap: comparison between immediate and delayed groups.

BACKGROUND: Breast reconstruction offers not only physical but also psychological rehabilitation. Autologous tissue transfer is a good option for breast reconstruction. The purpose of this study was to investigate the success rate, complications, and cosmetic outcomes following use of a muscle-sparing free transverse rectus abdominis myocutaneous (TRAM) flap for breast reconstruction. METHODS: Between August 1999 and February 2001, 15 consecutive patients underwent breast reconstruction using a muscle-sparing free TRAM flap after a mastectomy. Ten patients received mastectomies and immediately underwent breast reconstruction using muscle-sparing free TRAM flaps at Chang Gung Memorial Hospital. The remaining 5 patients first received a modified radical mastectomy and then underwent breast reconstruction. RESULTS: The mean age of patients was 43.9 (range, 32 to 50) years. Ten patients (67%) underwent immediate reconstructions, and 5 (23%) underwent delayed reconstructions. The overall success rate was 93.3%. Postoperative complications included 1 abdominal seroma and 1 small area of breast fat necrosis. Six of 10 patients with immediate reconstruction underwent both adjuvant chemotherapy and hormone therapy, while 3 patients received only chemotherapy. None of these adjuvant therapies were delayed by the reconstructive surgery. At a mean follow-up of 26.7 months, no local recurrence had been found, and 93% of patients were satisfied with the esthetic results. CONCLUSIONS: A muscle-sparing free TRAM flap is a good option for breast reconstruction. Both the success rate and patient satisfaction are high. The subsequent adjuvant therapy need not be delayed following immediate reconstruction.

Adult↗

PubMed2003

Nipple reconstruction in Asian females using banked cartilage graft and modified top hat flap.

Nipple reconstruction is usually the final stage of breast reconstruction and there are over 50 articles that describe different techniques. The majority of methods use local soft tissue as local flaps but they face the disadvantage of reduction in nipple projection after the initial two months. This is particularly troublesome in Asian females who may have wider nipples with prominent projection but small areola surface area. We developed a method to correct this problem using cartilage graft harvested during the initial breast reconstruction operation and banked beneath the skin flap. Using the modified 'top hat' flap, we found that no excess soft tissue is required to compensate for the reduction. We have used this method in 25 cases of nipple reconstruction and have obtained satisfactory result in projection.

Asia↗

PubMed2003

Chimeric flap in clinical use.

With the development of modern microsurgical reconstruction, there are several alternative methods for the complicated head and neck defect or injured extremity. The double-paddled flap, double flaps, and double flap with vascular flow-through linkage are good tools for extensive wide, composite, and three-dimensional defects. When faced with a difficult reconstruction, the expense, morbidity of the donor site, and operative time must be taken into consideration. Compared with other combined composite flaps and other methods, the chimeric flap has many advantages including: easy three-dimensional insetting, acceptable aesthetic appearance, reduced donor site morbidity, design with the least effort and operation time, and one pair of recipient vessel. The disadvantages of the chimeric flaps include: the variation of perforators, the requirement of a learning curve, and, sometimes, the need for a second venous drainage or shifting to double flaps. Overall, in selected cases, the chimeric flap is a good option for the reconstruction of extensive, composite, and three-dimensional defects.

Bone and Bones↗

PubMed2003

Breast cancer recurrence after immediate reconstruction: patterns and significance.

Local recurrence of cancer after mastectomy and immediate breast reconstruction is generally regarded as a poor prognostic indicator. This study was conducted to identify specific patterns of local recurrence following reconstruction and to determine their biological significance. The records of all patients who had undergone immediate breast reconstruction at The University of Texas M. D. Anderson Cancer Center between June 1, 1988, and December 31, 1998, were reviewed. The records of patients who had local tumor recurrence were then carefully analyzed. During this 10-year period, a local recurrence of cancer was found to have developed in 39 of 1694 patients (2.3 percent). Most recurrences were in the skin or subcutaneous tissue (n = 28; 72 percent), and the remainder were in the "chest wall" (n = 11; 28 percent), as defined by skeletal or muscular involvement. Transverse rectus abdominis myocutaneous flaps were used most often in both groups, but latissimus dorsi myocutaneous flaps and implant techniques were also used in some patients. Patients with subcutaneous tissue recurrence had an overall survival rate of 61 percent at follow-up of 80.8 months, compared with patients with chest wall recurrence, whose survival rate was 45 percent at similar follow-up. Metastases were less likely to develop in patients with subcutaneous tissue recurrence than in those with chest wall recurrence (57 percent versus 91 percent; p = 0.044); the former group also had a greater chance of remaining disease-free after treatment of the recurrence (39 percent versus 9 percent), respectively. Metastasis-free survival was higher in patients with subcutaneous tissue recurrence than with chest wall recurrence (2-year and 5-year survival: 52 and 42 percent versus 24 and 24 percent; p = 0.04). In both groups, the time to detection of the recurrence was similar (subcutaneous tissue recurrence, 27.1 months, versus chest wall recurrence, 29.5 months). Distant disease did not develop in one patient only in the chest wall recurrence group; this patient remained disease-free at 70 months. From these results, it was concluded that (1) not all local recurrences are the same: patients with subcutaneous tissue recurrence have better survival rates, a decreased incidence of metastases, and a greater chance of remaining disease-free than do those with chest wall recurrence; (2) immediate breast reconstruction (although potentially, it can conceal chest wall recurrence) does not seem to delay the detection of chest wall recurrence; and (3) even if a chest wall recurrence develops, it is highly associated with metastatic disease, and the survival rate is not likely to have been influenced by earlier detection. These data support the continued use of immediate breast reconstruction without fear of concealing a recurrence or influencing the oncologic outcome.

Adult↗

PubMed2003

The use of ultrasonography in preoperative localization of digital glomus tumors.

Small glomus tumors of the digits of the hand are difficult to excise and may be associated with relatively high rates of recurrence. This study was designed to prospectively evaluate the utility of preoperative ultrasound localization of such tumors to facilitate removal and to reduce recurrence rates. During a 5-year period, 34 patients clinically diagnosed with glomus tumors involving their digits were examined with high-resolution ultrasonography (5 to 9 MHz). Color duplex sonography was further applied if flow characteristics were identified. The ultrasound-predicted and actual intraoperative sizes were correlated and analyzed using the paired t test. Patients were followed for 1 to 6 years, and results were documented. Sonography showed a hypoechoic nodule with prominent vascularity between the nail body and the dorsal cortex of the distal phalanx in all subungual tumors. Complete resection was possible in all 35 glomus tumors, with assistance by accurate preoperative ultrasound localization. There was no long-term recurrence among the 29 patients available for evaluation 1 to 6 years postoperatively. Ultrasonography has great advantages in defining the exact location and size of the glomus tumor preoperatively. Prior knowledge of the exact site and size of the glomus tumor facilitates excision and appears to reduce rates of recurrence. The collaboration between hand surgeons and radiologists is useful to successfully treat glomus tumors of the digit.

Adult↗

PubMed2002

Behavior of free jejunal flaps after early disruption of blood supply.

We describe three free jejunal flaps that lost their axial blood supply in the early postoperative period--two flaps on the 7th day and the third on the 17th day. At 7 days, reestablishment of axial blood flow was essential to flap survival, whereas after 17 days, vascularization from the recipient bed was adequate to maintain viability. Based on these observations, a conservative approach to flap salvage for cases with pedicle disruption at 17 days or later is recommended.

Adult↗

PubMed2002

Microsurgical medialis pedis flaps for reconstruction of soft-tissue defects in the hand.

The medialis pedis flap (MPF) has been used for the reconstruction of soft-tissue defects in the hand since 1990. From January 1997 through January 2000, 19 patients (15 male, 4 female) with hand injuries underwent microsurgical MDF reconstruction at Chang Gung Memorial Hospital. There were finger injuries in 16 patients and palm defects in 3 patients. The mean patient age was 32.6 years (age range, 16-58 years). Flap size ranged from 4.5 x 2 cm to 7 x 6 cm (mean, 6 x 2.8 cm). Only one flap had partial loss. The donor site was closed primarily in 9 patients, and was closed using a split-thickness skin graft in 9 patients and a full-thickness skin graft in 1 patient. At a mean follow-up of 13 months, the protective sensation was 16 mm using the static two-point discrimination test and was 10 mm using the moving two-point discrimination test. Based on this retrospective study the authors conclude that (1) the MPF has the advantages of thin and glabrous skin, (2) the size of pedicle is compatible with the recipient vessel in the hand, (3) there is low donor site morbidity, and (4) achieving protective sensation is possible.

Adolescent↗

PubMed2002

Combined anterolateral thigh flap and vascularized fibula osteoseptocutaneous flap in reconstruction of extensive composite mandibular defects.

Extensive composite defects of the oromandibular area are usually created after the surgical treatment of T3 and T4 cancers, requiring complex reconstructive plastic surgical procedures. The preferred treatment method for this type of defect is reconstruction with two free flaps. The use of the vascularized fibula osteoseptocutaneous flap for the bone and inner lining defect is well known and accepted. Among the flaps that can be used for the outer lining and soft-tissue reconstruction, the two most commonly used have been the forearm flap and the rectus abdominis myocutaneous flap. However, these flaps have some disadvantages that restrict their use for this purpose. The forearm flap is usually too thin to cover the fibular bone and reconstruction plate, and the rectus abdominis myocutaneous flap can cause a subclinical reduction in abdominal strength. Both radial forearm and rectus abdominis myocutaneous flaps are difficult to harvest during tumor excision. Because of these drawbacks, over the past several years the authors have preferred to use the anterolateral thigh flap for outer face, neck, and submandibular region reconstructions. From October of 1998 to June of 2000, 22 extensive composite mandibular defect reconstructions using the free anterolateral thigh flap, combined with the vascularized free fibula osteoseptocutaneous flap, were performed at the Chang Gung Memorial Hospital. Complete flap survival was 90.9 percent (40 of 44 flaps). Complete loss was seen in an anterolateral thigh flap, which was then reconstructed with a pectoralis major myocutaneous pedicled flap (2.3 percent). There were five venous problems: three in osteoseptocutaneous free fibula flaps, the other two in anterolateral thigh flaps; all were revised immediately. However, the skin islands of two osteoseptocutaneous free fibula flaps and one anterolateral thigh flap developed partial necrosis (6.8 percent). The other complications were compartment syndrome in the leg in one patient, external carotid artery rupture in one patient, three donor-site infections in two patients, three neck wound infections, and one myocardial insufficiency; all were treated properly. Thirteen patients underwent revision procedures 6 months after the first operation. These procedures included debulking of the flap or revision of the mouth angle or both. Trismus or intraoral contraction was noted in none of these patients. In conclusion, the free anterolateral thigh flap combined with the vascularized fibula osteoseptocutaneous flap seems to be a good choice in the reconstruction of the extensive composite defects of the oromandibular region aesthetically and functionally.

Aged↗

PubMed2002

Reconstruction of through-and-through cheek defects involving the oral commissure, using chimeric flaps from the thigh lateral femoral circumflex system.

Repairing full-thickness cheek defects involving the oral commissure in the head and neck regions after tumor resection is a challenge for reconstructive surgeons. First, they are usually relatively large defects. Second, the axes of the cheek and intraoral lining are different from each other. Third, the shape and volume of the defect and the oral sphincter should be considered individually. Lateral femoral circumflex perforator flaps with at least two independent cutaneous perforators are suitable for reconstruction of such a defect in one stage. In this study, between January and December of 1999, a total of nine patients underwent reconstruction with chimeric lateral femoral circumflex perforator flaps immediately after resection of their oral cancers. The average age of the patients was 61 years (range, 42 to 74 years). The oral lining defects were between 5 x 5 cm and 6 x 12 cm in size, whereas the cheek defects were between 5 x 6 and 8 x 12 cm. Fifteen flaps were supplied by one perforator, and three flaps were supplied by two perforators. There were nine single arterial anastomoses, eight single venous anastomoses, and one double venous anastomosis. There were no total flap failures. One case of postoperative venous congestion was successfully treated by a second venous anastomosis. The average duration of hospitalization was 31.8 days (range, 18 to 49 days). The median follow-up time was 8.6 months, and all patients were alive at the time of evaluation. Six of nine patients had satisfactory or good contours of the cheek. Five of nine patients had normal deglutition. Six of nine patients had adequate oral continence. Compared with other free flaps, use of the combined (chimeric) lateral femoral circumflex perforator flaps for the reconstruction of cheek through-and-through defects involving the oral commissure has several advantages: (1) easy three-dimensional insetting, (2) a unique character suitable for the requirements of the oral lining and cheek skin to achieve good aesthetic appearance, (3) functional preservation of the oral sphincter and the resistance of gravity by use of the tensor fasciae latae, (4) minimal donor-site morbidity, (5) economic design, and (6) no need for microsurgical fabrication, because major vascular branches such as the transverse branch, the ascending branch, and the feeding branch to the rectus femoris muscle are not sacrificed in the procedure. The disadvantages of these flaps include (1) the complicated anatomy of the perforators, (2) the learning-curve requirement for their use, and (3) the occasional need for secondary venous drainage and shifts to double flaps. Although there are some difficulties, it was concluded that use of the chimeric lateral femoral circumflex perforator flaps in the selected cases is one of the good options available for the reconstruction of cheek through-and-through defects involving the oral commissure.

Adult↗

PubMed2002

Technique and strategy in anterolateral thigh perforator flap surgery, based on an analysis of 15 complete and partial failures in 439 cases.

The free anterolateral thigh flap is becoming one of the most preferred options for soft-tissue defect reconstruction. Between June of 1996 and August of 2000, 672 anterolateral thigh flaps were used in 660 patients in Chang Gung Memorial Hospital. A total of 439 flaps were cutaneous or fasciocutaneous flaps based on musculocutaneous perforators. The analysis of the flap failures was done only in this perforator series. In six cases, no suitable skin vessel was found during the dissection of the flaps. The complete success rate was 96.58 percent (424 of 439). Of the 15 failure cases, eight were complete and seven were partial (10 percent to 60 percent of the flap). Thirty-four flaps were reexplored, and 19 (56 percent) were salvaged. In this study, some of the reasons for the flap failure, unique to the anterolateral thigh perforator flap, were identified. They include inadvertent division of perforator at the fascial plane as a result of inadequate knowledge of perforator anatomy, inadvertent injury to the perforator during intramuscular dissection (noted by the surgeon or ignored) as a result of inexperience, and twisting of the pedicle during inset of the flap at the recipient site. Technical pearls in the harvest of the anterolateral thigh perforator flap are as follows: mapping of the skin vessels with a Doppler probe before flap design, meticulous dissection of the perforator under surgical loupe or even lower-magnification microscope, inclusion of a small fascia cuff around the perforator, and intermittent topical use of Xylocaine during the intramuscular dissection of the perforators. During reexploration, one must search for twisting of the pedicle and small bleeders from the branches of the intramuscular perforators.

Adolescent↗

PubMedDate not supplied

Ovine model for engineering bone segments.

We propose a large animal model for bone tissue engineering that yields quantitative data and simulates clinical methods and tissue needs. Skeletally mature domestic sheep (n = 20) were each implanted with three rectangular (1 x 1 x 4 cm), hollow tissue-molding chambers that were empty (control) or filled with equal weights (6.71-6.78 g) of particulate autologous bone graft (MBG) or bone graft that was autoclaved to denature stored growth factors (DeMBG). MBG provided scaffold and bioactive factors, and DeMBG provided only scaffold. The chambers were enclosed on five sides and securely implanted so that the open face was apposed to the osteogenic (i.e., cambium) layer of the rib periosteum for 3, 6, 9, 12, or 24 weeks, after which the chambers were harvested and the contents analyzed. Each chamber contained osseous and fibrovascular tissue. MBG-containing chambers had the best maintenance of tissue volume compared with DeMBG-containing or empty chambers, but it still decreased steadily over time. Despite this, the MBG-containing chambers showed continuous active bone formation. There was increasing calcified tissue with penetration of osteogenesis up to a mean of 0.75 +/- 0.15 cm from the periosteum by 9 weeks, and the osteogenic area peaked at 0.59 +/- 0.13 cm2 by 12 weeks. Using quantitative measures that reflect clinical needs (i.e., tissue volume, shape, and quality), it was possible to distinguish differences in performance associated with manipulation of implanted scaffold and bioactive factors. This ovine model may serve as a useful tool to develop clinical osseous tissue-engineering strategies.

Absorbable Implants↗