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51


TRAM flaps in patients with abdominal scars [Case Report]

Takeishi M; Shaw WW; Ahn CY; Borud LJ
Of 114 patients who had TRAM flap breast reconstruction, 46 (40 percent) had preexisting abdominal surgical scars. Sixty-six free TRAM flaps and 9 pedicled TRAM flaps were performed in the 46 patients. The records were analyzed to determine what impact, if any, abdominal scars had on postoperative complications. There were no reconstructive failures or significant (>25 percent) flap losses. Eight minor complications occurred in 7 patients (15 percent). The incidences of abdominal-wall weakness (4.3 percent), partial flap loss (4.3 percent), minor fat necrosis (4.3 percent), and donor-site wound problems (4.3 percent) were acceptable. Subcostal scars and multiple abdominal scars were found to predispose to skin complications. Right lower paramedian scars precluded free TRAM flaps because of damage to the inferior epigastric vessels in three of three patients. Both obesity (p = 0.003) and smoking (p = 0.05) were associated with a greater risk of wound-healing complications. We conclude that with certain technical modifications, TRAM flap reconstruction is a safe and effective procedure in patients with abdominal scars
PMID: 9047191
ISSN: 0032-1052
CID: 55622

Microbial evaluation: 139 implants removed from symptomatic patients

Ahn CY; Ko CY; Wagar EA; Wong RS; Shaw WW
Possible adverse effects of microbial organisms have been implicated in symptomatic silicone implant patients. In the literature, numerous authors have investigated the possible role of infection with respect to implant problems. To date, various bacterial species have been reported, including Staphylococcus aureus, Staphylococcus epidermidis, peptostreptococci, and Clostridium perfringens. Infections in polyurethane-coated prostheses also have been shown to prolong morbidity. Antibiotic use has been relatively empirical in this regard. The purpose of this study was, first, to determine the frequency, type, and clinical relevance of microbial colonization on implant surfaces removed from symptomatic patients and, second, to determine possible effects of microbial colonization on implant integrity (gel bleed, rupture). A total of 139 implants from 72 symptomatic patients were entered into the prospective clinical study between February of 1993 and July of 1994 at the UCLA Medical Center. The implant shell types included smooth (79 percent), polyurethane (8 percent), textured (7 percent), and smooth and Dacron (6 percent). The implant locations were subglandular (71 percent), submuscular (28 percent), and subcutaneous (1 percent). Of the 139 implants removed, 69 percent were intact and 31 percent were ruptured. Forty-seven percent of 139 implants were culture-positive. Propionibacterium acnes was isolated most frequently (57.5 percent), followed by Staphylococcus epidermidis (41 percent), and then Escherichia coli (1.5 percent). No fungal infections were identified. Culture positivity was not significantly associated with systemic symptoms. Sixty-seven percent of the positive culture implants were intact; 33 percent were ruptured. The frequency (47 percent) and types (P. acnes and S. epidermidis) of microbial colonization are determined in symptomatic silicone implant patients
PMID: 8942908
ISSN: 0032-1052
CID: 55623

Safe ischemia time in free-flap surgery: a clinical study of contact-surface cooling

Shaw WW; Ko CY; Ahn CY; Markowitz BL
Although the effectiveness of cooling in extending tolerable ischemia time is well-established experimentally, most free-flap surgeons are still concerned about this problem and try to limit the ischemic period to less than 1 hr. Clinically, contact-surface cooling has been used empirically to prolong the limits of ischemia time; however, its applications are unproven. It also remains unknown whether contact-surface cooling has detrimental effects on flap tissue, such as vessel spasm leading to thrombosis. The purpose of this study was to determine, in a clinical setting, if skin, muscle, and bone free flaps of considerable size could tolerate prolonged cold ischemia without adverse effects. Flap size, cold ischemia time, and surgical outcomes were studied in 189 consecutive free flaps. Microvascular thrombosis occurred in 5/378 (1.3 percent) of anastomoses. The overall flap complication/flap loss rate was 7/189 (3.7 percent). Mean ischemia time for all flaps was 2 hr and 6 min (range: 30 min to 5 hr, with one case at 6 hr and 8 min). The mean ischemia time for cases with flap complications was 2 hr 20 min, while ischemia time for cases with thrombosis averaged 2 hr 13 min. The one flap loss had an ischemia time of 1 hr 35 min. No statistically significant correlations existed between duration of ischemia time or duration of contact-surface cooling and the incidence of thrombosis, flap complication, or flap failure. Among the conclusions were that, within a 4-hr period of cold ischemia, the application of the surface-cooling technique is not detrimental to free flap surgery; thus, concern for ischemia, and especially the 'no reflow' phenomenon, generally should not interfere with efficient and orderly free-flap surgery
PMID: 8905540
ISSN: 0743-684x
CID: 55624

The use of cryopreserved microvenous allografts in the venous system without immunosuppression: an experimental study

Ahn CY; Narayanan K; Tran S; Monstrey S; Liang MD
Autogenous vein grafts are currently the number one choice in microsurgical practice for managing vessel length discrepancies. A significant percentage of these grafts is used in the venous system. Allografts may serve as a viable alternative source of vein grafts. Few studies in the past have described the use of cryopreserved vein grafts (1 mm in diameter) in the venous system. In the present study, we cryopreserved the femoral veins of rats and transplanted these across rat species (ACI to Lewis) as interpositional vein grafts into a defect in the femoral vein. Short-term patencies (21 days), expressions of systemic antigenicity, histology, and scanning electron microscopic studies were performed. We obtained 100% patencies with fresh control veins and cryopreserved veins at 21 days
PMID: 8863978
ISSN: 0148-7043
CID: 55625

Capsular synovial metaplasia as a common response to both textured and smooth implants

Ko CY; Ahn CY; Ko J; Chopra W; Shaw WW
Recent reports suggested that the presence of synovial metaplasia in the capsular tissues of breast implants is greater with textured-shelled implants compared with smooth. Textured implants, however, have become popular only in the last few years. Therefore, the studies do not address the possibility that synovial metaplasia may be a dynamic process related to time (e.g., implant age) rather than implant shell surface. In the current study, 159 implant capsules (85 patients) removed between February of 1992 and July of 1993 at UCLA Medical Center were evaluated histologically and correlated with clinical data, including the age of implants. Synovial metaplasia was identified in 40 percent (64 of 159) of the capsule specimens. A logistic regression analysis that removed the effect of implant age demonstrated no correlation of implant shell type (textured versus smooth) with the presence of synovial metaplasia. Gel bleed, implant location, pericapsular fluid, implant rupture, and capsular contracture also did not have any significant association with synovial metaplasia in the current study. The incidence of synovial metaplasia appears to decrease with age (77 percent at < 5 years; 22 percent at > 15 years). Our findings suggest that synovial metaplasia is not rare and in fact may be a fairly common transitional histologic finding. It may be part of the common progression that occurs at the implant-capsule interface. The clinical significance remains unknown
PMID: 8643727
ISSN: 0032-1052
CID: 55626

Cost and outcome of osteocutaneous free-tissue transfer versus pedicled soft-tissue reconstruction for composite mandibular defects

Talesnik A; Markowitz B; Calcaterra T; Ahn C; Shaw W
Thirty-nine patients underwent reconstruction of composite mandibular defects following resection for squamous cell carcinoma. Thirty-four underwent immediate reconstruction, while 5 were reconstructed secondarily. Twenty-one received soft-tissue reconstruction only with a pectoralis major myocutaneous flap, 14 underwent osteocutaneous free-tissue transfer, and 4 received a reconstruction plate with free-tissue transfer for soft-tissue coverage. The mandibular defects in the pectoralis major myocutaneous flap group tended to be posterolateral, while free-tissue transfer defects were more severe, usually involving the anterior mandible. Length of surgery and duration of intensive care unit care were significantly longer for free-tissue transfer patients, while flap complications were more common in the pectoralis major myocutaneous flap patients. Facial appearance scores were higher for the free-tissue transfer group by both patient and physician assessment. Social function, speech, and oral function did not differ significantly. Patients reconstructed secondarily with free-tissue transfer reported significant improvement in appearance, oral continence, and social function, with little change in speech intelligibility, deglutition, or diet tolerance. The cost of the main hospitalization was significantly higher in the free-tissue transfer group than in the pectoralis major myocutaneous flap group, although when the costs of subsequent hospitalizations are included, the difference in total cost narrows. Despite more adverse defects, free-tissue transfer provided more predictable aesthetic results and expeditious return to normal social function than did pectoralis major myocutaneous flap reconstruction. The fiscal impact of these complex reconstructions is, however, significant. Cost-containment issues are presented and recommendations are made
PMID: 8628799
ISSN: 0032-1052
CID: 55647

Clinical experience with a microvascular anastomotic device in head and neck reconstruction

DeLacure MD; Wong RS; Markowitz BL; Kobayashi MR; Ahn CY; Shedd DP; Spies AL; Loree TR; Shaw WW
BACKGROUND: Despite numerous refinements in microsurgical technique and instrumentation, the microvascular anastomosis remains one of the most technically sensitive aspects of free-tissue transfer reconstructions. MATERIALS AND METHODS: Concurrent with the development of microsurgical techniques, various anastomotic coupling systems have been introduced in an effort to facilitate the performance and reliability of microvascular anastomoses. The microvascular anastomotic coupling device (MACD) studied here is a high-density, polyethylene ring-stainless steel pin system that has been found to be highly effective in laboratory animal studies. Despite its availability for human clinical use over the last 5 years, reported clinical series remain rare. Our clinical experience with this MACD in 29 head and neck free-tissue transfers is reported herein. RESULTS: Thirty-five of 37 (95%) attempted anastomoses were completed with 100% flap survival with a variety of donor flaps, recipient vessels, and clinical contexts. Two anastomoses were converted to conventional suture technique intraoperatively, and one late postoperative venous thrombosis occurred after fistulization and vessel exposure. CONCLUSIONS: We conclude that the MACD studied here is best suited for the end-to-end anastomosis of soft, pliable, minimally discrepant vessels. Previous radiation therapy does not appear to be a contraindication to its use. Interpositional vein grafts may also be well suited to anastomosis with the device. When carefully and selectively employed by experienced microvascular surgeons, this MACD can be a safe, fast, and reliable adjunct in head and neck free-tissue transfer reconstructions, greatly facilitating the efficiency and ease of application of these techniques
PMID: 7485747
ISSN: 0002-9610
CID: 48970

Clinical significance of intracapsular fluid in patients' breast implants

Ahn CY; Ko CY; Wagar EA; Wong RS; Shaw WW
Clinical reports on the incidence and clinical significance of intracapsular fluid are lacking in the literature. It remains unknown whether the presence of intracapsular fluid has any relation to implant infection or colonization. The purpose of this study was to determine the frequency and type of intracapsular fluid, specifically, whether intracapsular fluid causes implant infection, implant rupture, or bacterial colonization. A total of 139 implants from 72 symptomatic patients were entered into the prospective clinical study. Our study demonstrated the presence of intracapsular fluid in 21 of 139 (15%) implants. Positive microbial cultures were identified in 39% of the implants in the positive intracapsular fluid group, compared to 43% in the negative fluid group. There was no statistically significant difference between these groups. Also, no adverse clinical relationship was demonstrated between local symptoms and presence of intracapsular fluid. There was, however, a positive trend toward the presence of fluid when implant shell types were nonsmooth (polyurethane and textured silicone implants). Further studies are indicated to elucidate the fluid production mechanism and possible secretory activity of prosthetic capsules interfacing the textured breast implant surface
PMID: 8579261
ISSN: 0148-7043
CID: 55627

Residual silicone detection using MRI following previous breast implant removal: case reports [Case Report]

Ahn CY; Shaw WW; Narayanan K; Gorczyca DP; DeBruhl ND; Bassett LW
The current controversy surrounding the safety of silicone gel breast implants has resulted in an increasing number being removed. Although previous reports have suggested that remnants of the implant capsule are reabsorbed after explantation surgery, the persistence of the capsule in fact may be associated with implant fragments and silicone gel leakage. In this study we have used magnetic resonance imaging (MRI) to identify residual silicone gel and silicone granulomas following the removal of silicone gel breast implants. Four representative clinical case reports are presented. These patients, who had residual silicone present in their bodies, presented to us with breast pain, palpable masses, or abnormal calcific mass densities apparent on a mammogram. High-resolution MRI images were found to be helpful in identifying local and remote collections of silicone gel, silicone granulomas, and residual capsules that were incompletely removed from previous explantation surgery. MRI breast images demonstrated high resolution and provided the accurate anatomical locations of residual silicone gel and silicone granulomas in all the regions of breast parenchyma, chest wall muscles, and axillae. Patients with persistent local symptoms following explantation surgery may benefit from an evaluation of the breast using MRI
PMID: 7484475
ISSN: 0364-216x
CID: 55628

Injected liquid silicone, chronic mastitis, and undetected breast cancer [Case Report]

Ko C; Ahn CY; Markowitz BL
Although the use of injected liquid silicone for breast augmentation has all but ceased since its widespread use in the 1960s, patients with injected silicone are still seen with a multitude of symptoms. Silicone mastitis is a well-documented phenomenon; however, there has been a paucity of information regarding cancer detection in this group of patients. We report 2 patients who presented with chronic mastitis but on further workup were found to have breast cancer. In both patients, early cancer detection was adversely affected by the presence of free liquid silicone. In view of this and other similar case reports, we advise that simple mastectomy be recommended to those patients with breasts inspissated with liquid silicone who not only have suspicious masses but present with recurrent mastitis or a family history of breast cancer
PMID: 7741437
ISSN: 0148-7043
CID: 55629