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Biomedical subjects

V L Young

Publications and source records attributed to V L Young.

At least 37 records · Page 2Linked to original sources
PubMed1996

Chemical, physical and mechanical analysis of explanted breast implants.

The chemical and biomechanical properties of explanted implants whose time of implantation ranged from zero to 21 years were measured. The properties appear to decrease with time. However it is important to note that proper controls have yet to be tested. The consistency of the gel varied considerably with manufacturer and date of manufacture. The data will be correlated with control samples when they become available. The data are consistent with the hypothesis that in some instances, the gel does affect the cross-linking, i.e., strength, of the silicone rubber shell. At the present time only a limited number of samples have been tested in this on-going program. One of our major objectives, to determine the influence of the physiological environment of the human body on the durability of the silicone implant, has yet to be quantified.

Breast Implants↗
PubMed1996

Bleed of and biologic response to triglyceride filler used in radiolucent breast implants.

Radiolucent breast implants filled with triglyceride oil have recently entered limited clinical trials. To investigate the questions of oil bleed and the fate of triglycerides that might escape from ruptured breast implants, experiments reported here used peanut oil labeled with radioisotopes so that it could be traced in the urine, feces, and organs of two groups of rabbits. In one experiment, 18 rabbits were implanted with peanut oil-filled implants labeled with tritium to determine whether triglycerides diffuse across silicone elastomer shells. In another experiment, 19 rabbits were injected with 14C-labeled peanut oil to study what might happen to the oil if an implant ruptures. At the end of the follow-up period, we measured radioisotope levels in tissue samples taken from the periprosthetic capsule or injection site of each rabbit, as well as from major organs and the subcutaneous fat on the dorsum opposite the experimental site. One experiment revealed that triglycerides do bleed across the implant shells. Tritium levels were highest in the implant capsule, the omentum, the aorta, and the subcutaneous fat on the nonexperimental side. In the experiment simulating implant rupture, 14C levels were above the background radiation count at the injection site and in the same tissue sites as in the bleed experiment. Both in vivo radiolabeling studies indicate that triglycerides freed from implants by means of bleed or rupture would be absorbed, metabolized, and either excreted or redistributed to the body's normal fat storage sites if they are not needed for energy. In a third in vitro experiment, triglyceride oil specimens were inoculated with various microorganisms associated with wound infections: Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus epidermidis, and diphtheroids. The data demonstrate that neutral triglycerides used as a breast implant filler do not support growth of common infection-producing bacteria and suggest that triglycerides may have bactericidal properties.

Adipose Tissue↗
PubMed1996

Development of alternative breast implant filler material: criteria and horizons.

The introduction of the silicone gel-filled breast implant more than 30 years ago changed the nature of alloplastic breast augmentation and reconstruction. Over the last three decades, it is estimated that one million American women have undergone implantation with some variation of these devices. Recent medical, legal, and regulatory developments have forced a moratorium on the unrestricted uses of the silicone gel-filled implants, and it appears unlikely that its general use will return. However, there is a continued need for some type of breast implant in both aesthetic and reconstructive surgery. The Food and Drug Administration has proposed testing guidelines for the development of any new breast implant before unrestricted clinical use. These guidelines will direct the creation of new filler materials from their earliest stages, through long-term postimplantation follow-up studies. This article succinctly examines the central issues in the breast implant controversy in relation to the FDA's recommendations for the development of new implants, discusses breast implant filler materials currently under development, and offers guidelines fro the development of breast implant fillers that are safe and effective.

Breast Implants↗
PubMed1996

Evaluation of the patient presenting with a painful wrist.

Wrist pain secondary to injury or disease is a common cause of morbidity and disability. The results of treatment are influenced strongly by promptly determining a correct diagnosis. We have found that a systematic, structured approach consisting of a detailed history and a thorough physical examination supplemented by the proper use of a variety of imaging modalities will establish accurately the diagnosis in almost all patients. Using such an algorithmic approach can greatly minimize medical costs and time lost from work as well as assist the surgeon in diagnosing the cause of wrist pain as quickly as possible. Even when this type of systematic approach is used in the evaluation of patients presenting with wrist pain, it is important for surgeons to remember that several imaging modalities, such as bone scans and arthrography, frequently demonstrate abnormal or atypical findings for which no pathologic correlate exists. If a firm diagnosis cannot be made even after a positive test result, it is unwise to perform surgery based solely on the findings of a test in the hope that wrist pain will thereby be relieved. In such cases, a trial of immobilization for 3 weeks is perhaps the best and most cost-effective way to verify that the pain is caused by an actual bone or joint abnormality that will respond to surgery.

Arthroscopy↗
PubMed1996

Cumulative trauma disorders.

The relationship between work activities and the diagnostic entities discussed in this article is poorly understood, but their development is probably multifactorial. The enormous cost to industry and society is driving many investigators to study the causes and pathologic manifestations of CTDs, and this research should lead to improved strategies for treating and preventing work-related injuries. Prevention, however, will work only if both management and labor participate in preventive efforts. When a task force approach can be implemented and senior management gives it the power to make effective changes, CTDs often can be reduced dramatically, as has been shown in numerous studies illustrating the success of this approach. It is unfortunate that many in senior management are reluctant to permit such task forces due to fear of increased injury claims. Our worry is that, in the end, the solution to problems believed to be associated with repetitive trauma at work may be shaped more by regulatory bodies and attorneys rather than scientists. Hand surgeons, who see patients with complaints that are perceived to be work related, often find themselves in the middle of this complicated problem, being asked to determine whether a patient's symptoms are caused by the performance of job tasks. To treat our patients with hand and wrist symptoms, we must stay abreast of the current understanding of CTDs and be familiar with the diagnosis and management of recognized disease entities such as those reviewed in this article. In most cases, a diagnosis of a specific clinical condition can be established that is based on strict criteria. If this is not possible and the picture is unclear, it is important not to guess at a diagnosis. Labeling a patient with a diagnosis such as thoracic outlet syndrome or nonspecific tendonitis without clear-cut and objective clinical signs can have lasting economic and employment consequences. For this reason, diagnosis of a specific clinical entity should be made only when the findings of the history, physical examination, and ancillary tests firmly support it.

Cumulative Trauma Disorders↗
PubMed1995

Detecting cumulative trauma disorders in workers performing repetitive tasks.

On-site testing of 157 poultry processors disclosed that 50% had three or more abnormal upper extremity findings out of a total of 22 possibles. The average worker had five to six abnormal findings. Impaired pinch strength, decreased vibration sensitivity in the fingertips, and reports of current numbness were the most prevalent. Of workers with signs, 25% reported no symptoms, whereas only 8% of workers reported symptoms but had no signs. The investigators concluded that this measurement method has utility for assessments of worker populations to determine prevalence of CTDs and, potentially, for preclinical detection of these disorders to permit early intervention, reduce medical costs, and minimize disability. The need for accurate measurement to enhance early detection and prevention is discussed.

Adult↗
PubMed1995

Paecilomyces variotii contamination in the lumen of a saline-filled breast implant.

This report describes a case of gross contamination with the filamentous fungus P. variotii cultured from an intraluminal saline breast implant removed from a patient 14 months after implantation because of severe capsular contracture. We suspect the fungal contamination occurred when a container of saline was left open in the operating room prior to filling and placement of the implant. This case may be the first documented report of microbial growth and reproduction in the internal environment of a saline implant. We assume that organisms such as P. variotii can survive--and accumulate biomass--on the minute amounts of substrates that diffuse across an implant envelope.

Breast Implants↗
PubMed1995

HLA typing in women with breast implants.

Since the 1970s, anecdotal reports have described a relatively small number of women who received silicone gel breast implants and later developed either a recognized rheumatologic disease or unexplained symptoms suggestive of an autoimmune disorder. The study reported here examined whether there is any association between the symptoms seen in implant patients and HLA molecules. One-hundred and ninety-nine subjects were evaluated by HLA typing: symptomatic patients with implants (group I, n = 77), asymptomatic women with implants (group II, n = 37), healthy female volunteers without implants (group III, n = 54), and fibromyalgia patients without implants (group IV, n = 31). A statistically significant 68 percent of group I were positive for HLA-DR53, compared with 35 percent of group II and 52 percent of group III. The fibromyalgia patients were strikingly similar to group I women in terms of HLA-DR molecules, with 65 percent of group IV being positive for DR53. Group I also had a statistically significant increased frequency of HLA-DQ2. Asymptomatic women with implants (group II) had an increased frequency of DR1 and DQ1. In addition, 42 percent of symptomatic patients with implants formed autoantibodies to their own B cells; of these, 81 percent were DR53-positive. Although frequencies of capsular contracture and implant rupture were not significantly different in the two groups with implants, there were statistically significant associations in group I between contractures and ruptures and the presence of DR53 and B-cell autoantibodies. These data suggest that symptomatic patients with implants share important genetic characteristics (primarily HLA-DR53 positivity) that differentiate them from their asymptomatic counterparts. DR53 may be a marker of women who are predisposed by their HLA genotype to develop symptoms following exposure to silicone gel breast implants.

Adolescent↗
PubMed1995

Facial reconstruction with prefabricated induced expanded (PIE) supraclavicular skin flaps.

The prefabricated induced expanded (PIE) supraclavicular flap refers to the staged transfer of an expanded supraclavicular skin with a fascia flap used as the carrier. In three patients, we utilized PIE supraclavicular flaps to successfully reconstruct a total forehead and two major nasal defects. Our first PIE flap confirmed the feasibility of the method but necessitated two microvascular free flaps. In the ensuing two patients, we reduced the need for microvascular anastomoses by using simple pedicled flap transfers in either or both stages. Whenever feasible, the preferred method consists of transferring a temporoparietal fascia flap to a subcutaneous pocket in the ipsilateral supraclavicular fossa and simultaneously placing a skin expander under both the fascia flap and the supraclavicular skin. After adequate expansion, the fascia becomes incorporated within the capsule of the expander, and the composite capsulofasciocutaneous flap can be safely transferred to the facial defect as the PIE flap. These patients show that supraclavicular PIE flaps can provide ample amounts of vascularized cutaneous tissue for the reconstruction of major facial defects. The necessary tissue is generated by expanding the most desirable tissue type available, and a selected vascular pedicle is induced to perfuse and carry that generated tissue. Compared with conventional expansion and adjacent flap transfers, PIE flaps allow the transfer of expanded skin to distant sites as island or free flaps perfused by the induced vascular pedicles.

Adolescent↗
PubMed1994

Diagnosis and treatment of accessory parotid gland masses.

Accessory parotid glands are true parotid tissue lying distinctly separate from the parotid gland proper. They lie along and drain into Stensen's duct. Although literature describing the accessory parotid gland is limited, its anatomy and pathology have been described. Controversies exist in the literature regarding the diagnosis and management of pathological changes seen in these glands. We have found magnetic resonance imaging to be extremely helpful in their diagnosis and treatment. A review of the literature and an illustrative example are presented.

Female↗
PubMed1994

Quantification of facial surface change using a structured light scanner.

Three-dimensional surface changes that accompany facial surgical procedures were measured noninvasively and evaluated quantitatively. An optical three-dimensional surface scanner with 360-degree surface coverage of a subject's head and a subsecond data acquisition was used. The scanner employs six pairs of "white light" pattern projectors and digital TV cameras. A noncontact optical method to quantify facial surface morphology and objectively assess change resulting from reconstructive or cosmetic plastic surgery has been developed. This quantification technique was implemented and tested with the three-dimensional range scanner. This technique defines the entire surface of the head and face, as opposed to the conventional manual method of measuring surface points or facial landmarks. The method allows facial volume change assessment. The method was tested by repeatedly scanning a volunteer who was injected subcutaneously with known volumes of anesthetic solution. The measured and injected volumes were compared and showed little difference.

Computer Graphics↗
PubMed1994

The efficacy of breast augmentation: breast size increase, patient satisfaction, and psychological effects.

In this study designed to quantify the degree of breast enlargement produced by augmentation mammaplasty, 112 women who underwent breast augmentation were interviewed. The size increase that typically resulted from various implant volumes was measured by comparing preoperative and postoperative bra sizes. For the study group as a whole, the average increase was two bra sizes (either increased cup size or a combination of increased cup size and chest circumference), regardless of the implant volume inserted. Patients also were asked a series of questions to evaluate the impact of the surgery on various psychological parameters, including body image, feelings of self-confidence, and interpersonal relationships. Along with having a very positive body image, the group reported decreased self-consciousness (86 percent) and heightened self-confidence (88 percent); in addition, 95 percent said they felt better about themselves after surgery. The women's satisfaction with the results of augmentation and the success of surgery in meeting their expectations also were measured. Eighty-six percent reported being completely or mostly satisfied with the postoperative results, 86 percent felt the operation was a complete success, and 95 percent said that augmentation met their expectations.

Adult↗
PubMed1993

Reduction mammoplasty for macromastia.

Macromastia is a common cause of physical and emotional suffering. Reduction mammoplasty can provide relief from shoulder grooving, back and neck pain, intertrigo, and symptoms of ulnar nerve compression. Similarly, emotional well being is enhanced by improved self-image, increased capacity to participate in sports and work, and the ability to wear normal, attractive clothes. In the last three years, we have performed reduction mammoplasty using the inferior pedicle technique or free nipple graft in 75 patients. Preoperative symptoms typically included back pain, shoulder grooving, and a stooped posture. Fat necrosis was the most common complication and was associated with large resections. Patient satisfaction was high for both procedures.

Adolescent↗