摘要:

After 30 years of clinical use, the 1992 Food and Drug Administration moratorium on silicone gel breast implants (SGBIs) resulted from a paucity of scientific data concerning their safety. The frequency of rupture and reoperative procedures was not known, nor were reliable data available for changes in the physical properties of shells and the composition of gels that might lead to SGBI failure. For this reason the authors conducted large-cohort meta-analyses of failure data for SGBIs based on numerous literature reports and also investigated systematically shell and gel properties from explanted SGBIs. They report their failure analysis data for more than 9,770 SGBIs (an update of an earlier study of more than 8,000 implants) as well an examination of the properties of shells and gels for 74 explanted SGBIs that ranged in age from 2 to 19 years (mean implanted age, 9.9 years). The explants tested were from several different manufacturers. For the modest-size explant cohort that was tested, 31 of 74 implants (42%) were found to be ruptured (some extensively). Even many intact shells were so weakened that only 51 shells had sufficient strength to enable preparation of samples for testing of mechanical properties and for analysis of composition by solvent extraction. Shells were found to contain 15 to 25% of extractable silicone. Exhaustive extraction of gels showed that they actually contained very little crosslinked silicone—85 to 95% being extractable soluble silicone fluid. Tensile and tear strengths of explanted silicone elastomer shells were lower than unimplanted prostheses and were generally well below reported manufacturers’ values. This updated large-cohort failure analysis continues to show that shell rupture is related directly to implant duration (e.g., from analysis of variance statistics, 26% failure at 3.9 years, 47% at 10.3 years, 69% at 17.8 years;p≤ 0.001). However, for the relatively small series of explants for which physical property data are reported, no significant correlation was observed between implant duration and the degradation of implant strength. It therefore appears most reasonable to conclude that after early weakening of shells as a result of swelling of the shell elastomer by diffusion of silicone oil from the gel, SGBI failure can occur in a time-dependent manner as a result of continuing implant motion and cyclic stresses that are exacerbated by stress concentration at thin areas, defects, and folds in the shells.

ISSN:0148-7043    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

The latissimus dorsi flap is enjoying resurgence in interest for breast reconstruction. A technique is described in which the pedicled latissimus dorsi flap (the whole muscle and overlying fat is harvested) is molded to resemble the shape of a breast. This enhances the shape and projection of the reconstructed breast, and prosthesis is no longer required. The disadvantages of the technique are the longer scar that is required to harvest all the muscle and overlying fat, and that there is still some limitation to the size of the breast that can be reconstructed. Harvesting the extended latissimus dorsi flap also leaves a contour defect on the back.

ISSN:0148-7043    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

A clinical study of the incidence of vascular complications in free and supercharged pedicled transverse rectus abdominis musculocutaneous (TRAM) flaps was undertaken. The complications associated with each of these two TRAM flaps were assessed. The incidence of vascular complications in the supercharged pedicle was found to be twice that associated with the free TRAM flap (36% vs. 18%); however, these results did not reach significance (p= 0.2). Fat necrosis was the most common complication in each group, with the overall rate being 17%. The incidence in the supercharged TRAM flap (29%) was more than twice that in the free TRAM flap (13%;p= 0.2). Partial flap loss was also greater in the charged flap than in the free flap (14% vs. 3%,p= 0.1). The results, however, did not reach significance, and this may be related to the relatively small sample size (52 patients). Vein grafts were used more often in the supercharged pedicled TRAM flap (p= 0.02). Obesity was also associated more frequently with the supercharged pedicled TRAM flaps (p= 0.07). Other risk factors were nearly equally distributed between either type of the flap. The results of the study support the continued use of the free TRAM flap. There appears to be no additional advantage in charging the pedicled TRAM with a microvascular anastomosis because the results were found to be inferior to those of the free TRAM flap. Other clinical factors, however, may dictate the type of flap used. A larger series is required to assess the importance of each of the risk factors affecting flap survival.

ISSN:0148-7043    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Several studies have shown that mastectomy causes psychosocial disturbances and problems with body image. Patients experience inconvenience with an external prosthesis. Reconstruction can correct these disturbances and make prosthesis redundant. This prospective study was designed to evaluate satisfaction among women who underwent delayed breast reconstruction. The study population consisted of 75 women operated at Töölö Hospital from August to December 1999. Sixty-seven operations were free microvascular transverse rectus abdominis musculocutaneous reconstructions and eight were latissimus dorsi flap reconstructions. The response rate was 80% at both 3 and 6 months postoperatively. The main reason why the women sought reconstruction was the inconvenience of the prosthesis. Preoperative expectations were fulfilled in 90% of patients. An overwhelming majority expressed satisfaction with the outcome. The most often reported benefit was having a new breast of one's own. The main drawbacks were the difficult operation and the unexpectedly long recovery time. Reconstruction alleviated markedly neck, shoulder, and back pain. There was no change in patient self-esteem but there was a substantial positive change in how they felt about their looks. The authors suggest that breast reconstruction should be offered as an option to all women undergoing mastectomy.

ISSN:0148-7043    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

The desire to modify a person's outer appearance is a phenomenon that can be traced back to the beginning of humankind. Body modifications have been practiced among all cultures around the globe to differing extents. The authors present medical complications through jewelry in a series of 35 consecutive patients. Patient charts were evaluated for age, gender, type and sequelae of injury, complications, and treatment results. The male-to-female ratio was 1:2.2. Most of the recorded complications were related to the new vogue of piercing, with the ear affected most commonly. Usually the complications were minor; however, 2 patients sustained disfiguring damage to their auricular cartilage as a result of high ear piercing, a child nearly asphyxiated on an aspirated earring, and 2 patients experienced severe dysphagia as a result of tongue piercing. The most severe complication was a lethal strangulation injury in a female patient whose necklace got trapped in the headrest of her car seat during a front-end collision.

ISSN:0148-7043    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

The efficacy of allogeneic perforated demineralized bone matrix with autogenous bone paste in the treatment of full-thickness cranial defects was evaluated in 10 consecutive patients between June 1998 and December 1998. The skull defects resulted from trauma in 9 patients and removal of a cranial tumor in 1 patient. The size of the skull defects ranged from 8 × 6 cm to 11 × 12.5 cm. Follow-up averaged 33 months for all patients. Postimplantation evaluations included serial photographs, repeated physical examination, and three-dimensional computed tomography for all patients. Visual inspection of the implanted biomaterial 6 months later was possible in 1 patient. The contour of the reconstructed skull was acceptable aesthetically without any secondary depression noted during the follow-up period. Three-dimensional computed tomographic scans taken 2 years after implantation indicated that the allogeneic perforated demineralized bone matrix provided a matrix for new bone formation with remarkable osteoinductive potential for new bone formation. The autogenous bone paste was able to caulk the demineralized bone matrix and fill the contour irregularities and gaps of the reconstructed cranium. The results from this clinical study indicated that allogeneic perforated demineralized bone matrix with autogenous bone paste is a promising alternative to an autogenous bone graft and or alloplastic material for cranioplasty.

ISSN:0148-7043    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

The authors present a new model for microsurgical training of venous anastomosis—namely, the dorsal penile vein of the rat. In 12 male Wistar rats weighing 220 to 290 g, the anatomy of the dorsal penile vein was studied by dissection and histology. Anatomic dissection studies revealed that the dorsal penile vein has an average diameter of 1.4 mm (range, 1.2–1.6 mm) without tendency to collapse. The vein could be dissected for an average segment of 25 mm without any branches, allowing easy dissection and approximator clamp placement. Comparison of its cross-section with that of the femoral vein histologically by light microscopy and scanning electron microscopy revealed a larger diameter and much thicker vessel wall with a prominent tunica media and adventitia. Based on the findings of the anatomic study, the dorsal penile vein anastomotic model was created in the rat. In 20 animals, the vein was divided sharply in its midsection and was anastomosed end-to-end using standard microsurgical technique. Results indicated a 100% patency rate immediately after the anastomosis and a 90% patency rate (18 of 20) 1 week after the procedure. This model offers the advantages of easy dissection without ligation of any side branches and a thick vessel wall without a tendency to collapse. Moreover, a major limb vein is not sacrificed. It is concluded that this new model may better simulate the clinical procedure of microvenous anastomosis because it presents similarities to human veins.

ISSN:0148-7043    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Primary repair of a high ulnar nerve injury results in a uniformly poor outcome as a result of the great distance between the site of injury and the innervated muscles. In this study the authors present two cases of high ulnar nerve injuries in adults. Reconstruction was performed using the distal branch of the anterior interosseous nerve, which was transferred to the distal motor branch of the ulnar nerve. This resulted in timely return of function to the ulnar-innervated intrinsic muscles of the hand, which was documented further by electromyography. For high ulnar nerve injuries, this type of nerve transfer is a much better approach than the traditional primary neurorrhaphy.

ISSN:0148-7043    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Wound closure in open surgery is a fundamental skill acquired early during the surgeon's career. Individual modifications are adopted frequently by the more experienced surgeon in an effort to increase efficiency. To date, there has been no objective measurement regarding whether these modifications significantly impact economy of movement or procedure time. The advent of the Imperial College Surgical Assessment Device (ICSAD) allows standardized, objective evaluation of a novel suture technique for wound closure (study group) developed by one of the senior authors (DBH) and compares the technique to the current method taught by the Royal College of Surgeons of Great Britain and Ireland (control group). Ten surgical registrars underwent both tasks in a standardized manner for five repetitions. Mean total movements and duration of procedure were decreased significantly for the study group (analysis of variance:p= 0.018 andp= 0.033 respectively) with an economy index (total movements/total time) of 0.79 movements per second for the control group vs. 0.67 for the study group. This study demonstrates ICSAD's usefulness in defining a novel suture technique as a more efficient method of cutaneous closure than the currently advocated technique.

ISSN:0148-7043    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Extravasation of a chemotherapeutic agent is one of the most frequent complications in cancer patients. Full-thickness skin necrosis often occurs after extravasation. Alternative approaches to treatment are local wound care, elevation, and hypothermia. It was shown that heparin prevents skin necrosis. In this experimental study, the effects of heparin fractions on the prevention of skin necrosis were compared by applying an extravasation model of Adriamycin in rats. Forty Sprague–Dawley male rats weighing 250 to 300 g were used. A total of 0.3 ml doxorubicin hydrochloride was administered subcutaneously to all rats. Ten minutes later, in the control group (group I), 1 ml normal saline was administered subcutaneously. In the first experimental group (group II), 100 U per day heparin sodium was administered in a volume of 1 ml subcutaneously. In the second experimental group (group III), nadroparin calcium (5 anti-Xa U per kilogram per day) was administered. In the third and last experimental group (group IV), dalteparin sodium (5 anti-Xa U per kilogram per day) was administered. All drugs were administered for 2 weeks. Necrotic areas were measured 4 weeks later. Statistical analysis was performed using the Kruskal–Wallis analysis of variance and the Mann–WhitneyUtest. Heparin fractions caused a decreased ulcer rate and size than controls (p< 0.05). There was no superiority among heparin fractions. The authors think that low-molecular weight heparins are preferred, considering the higher risk of bleeding with unfractionated heparin.

ISSN:0148-7043    

出版商:OVID    

年代:2002

数据来源: OVID