Hilton M. Kaplan

Managing late periprosthetic fluid collections (seroma) in patients with breast implants: a consensus panel recommendation and review of the literature.

Background: The goal of this consensus is to establish an algorithm for the management of patients who develop a late or delayed periprosthetic fluid collection. A work group of practicing plastic surgeons and device industry physicians met periodically by teleconference and discussed issues pertinent to the diagnosis and management of late periprosthetic fluid collections in patients with breast implants. Based on these meetings, treatment recommendations and a treatment algorithm were prepared in association with an editorial assistant. Method: The work group participants discussed optimal care approaches developed in their private practices and from evidence in the literature. Results: The consensus algorithm and treatment and management recommendations represent the consensus of the group. Conclusions: The group concluded that late periprosthetic fluid collection (arbitrarily defined as occurring ≥1 year after implant) is an infrequently reported occurrence (0.1 percent) after breast implant surgery and that, at a minimum, management should include clinically indicated ultrasound-guided aspiration of fluid, with appropriate cultures and cytologic testing. Further evaluation and additional treatment is recommended for recurrence of periprosthetic fluid collection after aspiration, or clinical suspicion of infection or neoplasia.

Design and Fabrication of an Injection Tool for Neuromuscular Microstimulators

The injection of small implants into precisely localized sites within the body is a difficult task usually undertaken by surgeons or interventive radiologists. We have designed, produced and tested a simple tool for implanting BION™ wireless microstimulators as an outpatient office procedure. The ability of BIONs to elicit a desired muscle contraction depends on their placement near the motor fibers that innervate the muscle fibers, providing both the requirement and a means for achieving accurate placement. The implant is preloaded into the tip of the cannula of a two-piece insertion tool made from non-conductive polymers. Trial stimulation pulses are generated by the implant as the tool is manipulated into the desired position. The implant is released by withdrawing the cannula over the implant, preserving both the relative location of the implant’s electrodes with respect to the target and determining its desired axial orientation, which is important for implants containing motion sensors. The BION Insertion Tool has been used for over 30 BION implants in human subjects to date.

Percutaneous collagen induction–regeneration in place of cicatrisation?

BACKGROUND Ablative procedures that are used for the improvement of a degenerative process that leads to a loss of skin elasticity and integrity, injure or destroy the epidermis and its basement membrane and lead to fibrosis of the papillary dermis. It was recently shown in clinical and laboratory trials that percutaneous collagen induction (PCI) by multiple needle application is a method for safely treating wrinkles and scars and smoothening the skin without the risk of dyspigmentation. In our study, we describe the effect of PCI on epidermal thickness and the induction of genes relevant for regenerative processes in the skin in a small animal model. METHODS The purpose of this study in a rat model was to determine the effects of PCI on the skin both qualitatively and quantitatively. The epidermal and dermal changes were observed by histology and immunofluorescence. The changes in gene expression were measured by array analysis for cytokines, such as vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF)-7, epidermal growth factor (EGF) and extracellular matrix molecules such as collagen type I and type III. RESULTS The present study showed that PCI with topical vitamins resulted in a 140% increase in epidermal thickness; an increase in gene and protein expression of collagen I, glycosaminoglycans (GAGs) and growth factors such as VEGF, EGF and FGF7. The collagen fibre bundles were increased, thickened, and more loosely woven in both the papillary and reticular dermis. CONCLUSION We were able to show that PCI modulates gene expression in skin of those genes that are relevant for extracellular matrix remodelling.

Risk of lymphoma in women with breast implants: analysis of clinical studies.

Large studies suggest that the overall rate of lymphoma in women with breast implants is no greater than in the general population; clinical reports suggest an association between breast implants and the rare non-Hodgkin lymphoma, anaplastic large cell lymphoma (ALCL). Observed cases of lymphoma reported in Allergan-sponsored breast implant clinical studies were compared with expected cases on the basis of the incidence of lymphoma among women in the National Cancer Institute’s Surveillance Epidemiology and End Results program, using standardized incidence ratios (SIRs) and 95% confidence intervals (CIs). In clinical studies, there were 28 observed cases of lymphoma among 89 382 patients and 204 682 person-years of follow-up compared with 43 expected cases [SIR: 28/43=0.65 (95% CI: 0.43–0.94), P=0.02]. SIRs were calculated stratifying by baseline cancer history: women without prior cancer [SIR: 17/24=0.70 (95% CI: 0.41–1.13), P=0.17] and women with prior cancer [SIR: 11/14=0.79 (95% CI: 0.39–1.41), P=0.52]. SIRs were calculated by implant shell type: textured shell implants [SIR: 16/23=0.70 (95% CI: 0.40–1.13), P=0.16] and smooth shell implants [SIR: 12/19=0.63 (95% CI: 0.33–1.10), P=0.12]. Surveillance Epidemiology and End Results reported 12 cases of primary breast ALCL in women between 1996 and 2007 without a history of cancer, for an average annual incidence of 4.28 (95% CI: 3.51–5.05)/100 million women in the US – these women may or may not have breast implants. In clinical studies, three ALCL cases were reported in women with breast implants and a history of breast cancer, yielding a crude incidence rate of 1.46 (95% CI: 0.30–4.3)/100 000 person-years. Large clinical studies, based on over 200 000 person-years of follow-up, suggest no evidence of an increased risk of lymphoma among women who have received breast implants.

Clinical Trial Outcomes of High- and Extra High–Profile Breast Implants

BACKGROUND Clinical data concerning potential risks and benefits associated with the use of high- and extra high-profile breast implants are lacking. OBJECTIVES The authors assess the risk of adverse events (AE) with high- and extra high-profile breast implants compared with low- to moderate-profile breast implants in patients enrolled in long-term clinical studies. METHODS Relative risks (RR) of capsular contracture (CC), moderate to severe malposition, and secondary procedure were calculated using Cox proportional hazards regression, adjusting for patient, procedure, and device characteristics among patients enrolled in the primary augmentation cohorts of the Core (NCT00689871; round, silicone-filled implants) and 410 (NCT00690339; shaped, highly cohesive silicone-filled implants) clinical studies. Study pooling provided comparisons of implant shape and fill, as well as contributed to relative outcome. Analyses were also stratified by preoperative breast measures. RESULTS In the Core study (N = 454; 907 implants; mean follow-up 7.2 years; 3669 person-years), and the combined Core and 410 studies (N = 4412; 8811 implants; mean follow-up 3.0 years; 14 528 person-years), risk of CC, secondary procedures, and mastopexy as a secondary procedure were reduced in high-profile versus low- to moderate-profile breast implants (P < .05). The risk of moderate to severe malposition was not significantly different between high-profile and low- to moderate-profile breast implants in the Core or combined studies (RR, 0.58 [95% confidence interval (CI), 0.22-1.51] and RR, 0.72 [95% CI, 0.31-1.70], respectively). Analyses stratified by preoperative breast measures did not indicate higher risk of CC, malposition, or secondary procedure among patients with either smaller (<17 cm) or larger (≥17 cm) preoperative measures. CONCLUSIONS Among primary augmentation patients with round, silicone-filled, or shaped, highly cohesive silicone-filled implants, high- and extra high-profile implants were associated with lower risks of CC, secondary procedures, and mastopexy and were not associated with greater risks of moderate to severe malposition versus low- to moderate-profile implants. LEVEL OF EVIDENCE 3.

Preventing ischial pressure ulcers: I. Review of neuromuscular electrical stimulation

Objective: Pressure ulcers PUs are common and debilitating wounds that arise when immobilized patients cannot shift their weight. Treatment is expensive and recurrence rates are high. Pathophysiological mechanisms include reduced bulk and perfusion of chronically atrophic muscles as well as prolonged occlusion of blood flow to soft tissues from lack of voluntary postural shifting of body weight. This has suggested that PUs might be prevented by reanimating the paralyzed muscles using neuromuscular electrical stimulation NMES. A review of the published literature over the past 2 decades is detailed. Outcomes: Historically gluteus maximus GM has been an important target for NMES, but results have been difficult to interpret and suitable technology has been lacking. Conclusions: NMES of the buttock muscles appears to be valuable in terms of its trophic effects, improving vascularity and soft tissue bulk. It remains unclear, however, whether GM can actually achieve sufficient unloading of normal forces to permit blood flow in the capillary beds of the skin and muscle. Analysis of the skeletal biomechanics is required to assess the relative value of GM vs. hamstring HS hip extensors in this regard.

Preventing ischial pressure ulcers: III. clinical pilot study of chronic neuromuscular electrical stimulation

Objective: BIONs™ BIOnic Neurons are injectable, wireless microstimulators that make chronic BION Active Seating BAS possible for pressure ulcer prevention PUP. Neuromuscular electrical stimulation NMES produces skeletal motion and activates trophic factors, counteracting three major etiological mechanisms leading to pressure ulcers PUs: immobility, soft-tissue atrophy, and ischemia. Companion papers I and II reviewed prior experience with NMES for PUP, and analyzed the biomechanical considerations, respectively. This paper presents a treatment strategy derived from this analysis, and the clinical results of the first three cases. Methods: Two BIONs implanted one on inferior gluteal nerve to gluteus maximus GM, and other on sciatic nerve to hamstrings HS, in 3 spinal cord injured SCI subjects already undergoing gluteal rotation flaps for PUs. BAS using HS when seated, and BION Conditioning BC via GM+HS when non-weightbearing. Follow-up: 1 yr, including 6 mo. treatment window interface pressure mapping; muscle perfusion scans; MRI, X-ray volume assessments. Results: Successfully implanted and activated both desired muscle groups, selectively, in all. No PU recurrences or wound complications. Two subjects completed protocol. Mean results: Interface: contact pressure -10%; maximum pressure -20%; peak pressure area -15%. Vascularity: GM +20%, HS +110%. Perfusion: GM +70%, HS +440%. Muscle volume: GM +14%, HS +31%. Buttock soft-tissue padding: +49%. 1 BION failed; 1 BION rotated under GM. Conclusions: Promising proof-of-concept data supporting the feasibility of implanted microstimulators to achieve sufficiently strong and selective activation of target muscles for PUP. Ultimate goal is prophylactic deployment through bilateral, nonsurgical injection of BIONs in chronically immobile patients.

Weight shifts by the electrical stimulation in seating for the prevention of pressure ulcer

Pressure ulcer is the injury state by continuous normal or shear stress on the skin for spinal cord injury(SCI) patients. Even though functional electrical stimulation recently receives much attention as a promising method for the pressure ulcer prevention in plegic patients or elderly people, its protocol has not been developed yet. In order to determine which muscle can be stimulated for the pressure ulcer prevention, pressure distributions on the buttock and thigh by the functional electrical stimulation on gluteus maximus, sartorius and hamstring in the seating posture were analyzed. Ten normal young male volunteers who have no physical problem and are able to take normal sitting posture participated in the experiment. Muscles were stimulated once per five seconds, totally six times during thirty seconds by the MP150 stimulator. Ground reaction force and pressure distribution on the stimulated buttock and thigh increased when gluteus maximus was stimulated. Pressure on the stimulated thigh slightly decreased with the individual stimulation of sartorius or hamstring. When both gluteus maximus and sartorius were stimulated at the same time, pressure on the unstimulated buttock and thigh decreased significantly. With the simultaneous stimulation of sartorius and hamstring, both pressure on the stimulated thigh and ground reaction force significantly decreased. Results showed that due to the electrical stimulation, the body weight transferred to the stimulated side and the pressure of the opposite side relatively decreased. There are more synergistic effects on the weight shift, when glueteus maximus is stimulated simultaneously with sartorius or hamstring. In spite of the limitation of surface electrical stimulation on healthy subjects, this study would be very useful to prevent pressure ulcer and select the muscles to stimulate effectively for the elderly and spinal cord injury patients.

Clinical applications of BION/sup TM/ microstimulators

Injectable, wireless microstimulators have the potential to provide low-cost and easily administered electrical stimulation to a variety of neuromuscular sites for a variety of clinical disorders. We are studying one version of this new technology platform in several different clinical studies currently underway or in the final stages of preclinical development. Preliminary results suggest that the approach is safe and effective for muscle activation. They also suggest enhancements of the technology that should improve its ease and reliability of use.

Preventing ischial pressure ulcers: II. Biomechanics

Background: Pressure ulcers PUs are common and debilitating wounds that arise when immobilized patients cannot shift their weight. Neuromuscular Electrical Stimulation NMES has been investigated for Pressure Ulcer Prevention PUP for over 20 years. Historically gluteus maximus GM has been considered an important actuator in attempting to redistribute seated pressures through NMES. Methods: Analysis of skeletal biomechanics to quantify the value of GM relative to hamstring hip extensors HS, using muscle moment models based on torques and rigid body mass estimates from the literature. Surface stimulation experiments n = 10 + 1, non-paralyzed to validate model and identify promising stimulation sites and treatment strategies that would approximate healthy biomechanics. Results: Literature values and Rigid Body Analysis estimate: ~63 Nm extensor torque requirement calculated for complete ipsilateral unloading of the buttocks. Muscle Moment Analysis: GM can provide 70% of total hip extensor torque when walking vs. 18% when seated. HS can provide 100 Nm hip extension torque when seated, exceeding 63 Nm requirement. Surface Stimulation: ipsilateral seated interface pressure mean -26% during HS stimulation vs. +16% with GM; peak pressure area -94% HS vs. +213% GM. Conclusions: GM activation reduces disuse atrophy and improves circulation, but appears neither required, nor desired, for unloading when seated. HS stimulation alone should be capable of sufficient unloading. This new proposed approach is explored clinically in companion paper III.