Secondary "Hybrid Reconstruction" Concept with Silicone Implants After Autologous Breast Reconstruction - Is It Safe and Reasonable?

BACKGROUND The use of autologous tissue for breast reconstructive surgery following mastectomy has become routine and allows for excellent symmetry and aesthetic results. However, in some cases, the amount of tissue available from the utilized flaps is not enough to achieve the desired outcome. The use of autologous fat grafting, as well as other techniques, has been described to deal with such problems. However, though well-established, these techniques may also fail to achieve the desired results. The aim of this study was to highlight the opportunity to improve aesthetic results using a secondary prosthesis underneath the previously used free flap and to examine whether this is a safe and reasonable procedure. MATERIAL AND METHODS In our study we included patients with unsatisfied aesthetic results after free flap procedures (DIEP, S-GAP, TMG, and FCI) between 2011 and 2018. In each case described, a secondary prosthesis was placed underneath the original flap in order to improve symmetry, shape and projection. Patient age, indication for surgery, adjuvant therapy, complications and outcomes have been registered. A 12-point scale was established to analyze patient satisfaction and aesthetic outcome. RESULTS Overall "operative success" was achieved in all 13 patients (14 flaps) evaluated. At 12 months after reconstruction, all aesthetic scores collected were between good and excellent. In contrast to other studies, we chose a secondary approach for the flap augmentation and we used the epipectoral pocket for the placement of the implant. In our series, low rates of early and late post-operative complications were observed, with a high overall rate of satisfaction. CONCLUSIONS The demonstrated "Hybrid Breast Reconstruction" approach, using an implant underneath a free flap autologous breast reconstruction, provided a safe and reliable option to optimize breast reconstruction outcomes.

Does Decreased Surgical Stress Really Improve the Psychosocial Health of Early-onset Scoliosis Patients?: A Comparison of Traditional Growing Rods and Magnetically-controlled Growing Rods Patients Reveals Disappointing Results.

STUDY DESIGN: Cross-sectional case-control study. OBJECTIVE: Compare psychosocial profile of magnetically-controlled growing rod (MCGR) patients to traditional-growing rod (TGR) with an array of psychiatric tools, expecting improvement in MCGR due to decreased number of surgical procedures. SUMMARY OF BACKGROUND DATA: TGR treatment has had positive clinical and radiographic results; however, upward of 10 surgical sessions and high complication rates have called into question the quality of life of these children. Improvement with the introduction of the MCGR is expected. METHODS: GR patients with minimum of 2-years follow-up were recruited. None had neurological conditions. All underwent testing with the Wechsler Intelligence Scale for Children-Revised, and only those in the normal range were included. Patients filled out questionnaires with mental health professionals to measure psychosocial status. MCGR patients' results were compared to TGR patients. RESULTS: Twenty-seven patients met criteria (10 MCGR, 17 TGR): average age at enrollment 11.8 years (range 5.9-17). MCGR group was significantly younger (9.1 vs. 13.3 yr) and had significantly shorter follow-up (45.6 vs. 82.8 mo) (P < 0.05). TGR patients underwent an average of 16 surgical procedures, MCGR an average of 1.5 (including complications, P < 0.05). Age at index surgery (6 yr), preoperative and postoperative major curve magnitudes (60°, 40° respectively) were statistically similar.There was no difference in current psychiatric diagnoses between the groups. MCGR patients scored worse than TGR patients in general functionality domains. TGR patients showed increased functionality and prosocial scores with increased number of procedures. This effect was not observed in MCGR. CONCLUSIONS: The expected improvement in psychosocial status with the MCGR was not observed at a 31.6-month-follow-up. It appears that provided the patient spends enough time in the treatment process to notice benefit and does not experience major complications, noninvasiveness of lengthening procedures does not show up as an advantage with the psychosocial tools utilized in this study. LEVEL OF EVIDENCE: 3.

Recovery Kinetics of Radiographic and Implant-Related Revision Patients Following Adult Spinal Deformity Surgery.

BACKGROUND: Prior studies have observed similar health-related quality of life (HRQL) in revisions and nonrevision (NR) patients following adult spinal deformity (ASD) correction. However, a novel comparison approach may allow better comparisons in spine outcomes groups. OBJECTIVE: To determine if ASD revisions for radiographic and implant-related complications undergo a different recovery than NR patients. METHODS: Inclusion: ASD patients with complete HRQL (Oswestry Disability Index, Short-Form-36 version 2 (SF-36), Scoliosis Research Society [SRS]-22) at baseline, 6 wk, 1 yr, 2 yr. Generated revision groups: nonrevision (NR), revised-complete data (RC; with follow-up 2 yr after revision), and revised-incomplete data (RI; without 2-yr follow-up after revision). In a traditional analysis, analysis of variance (ANOVA) compared baseline HRQLs to follow-up changes. In a novel approach, integrated health state was normalized at baseline using area under curve analysis before ANOVA t-tests compared follow-up statuses. RESULTS: Two hundred fifty-eight patients were included with 50 undergoing reoperations (19.4%). Rod fractures (n = 15) and proximal joint kyphosis (n = 9) were most common. In standard HRQL analysis, comparing RC index surgery and RC revision surgery HRQLS revealed no significant differences throughout the 2-yr follow-up from either the initial index or revision procedure. Using normalized HRQL/integrated health state, RI displayed worse scores in SF-36 Physical Component Score, SRS activity, and SRS appearance relative to NR (P < .05), indicating less improvement over the 2-yr period. RC were significantly worse than RI in SF-36 Mental Component Score, SRS mental, SRS satisfaction, and SRS total (P < .05). CONCLUSION: ASD patients indicated for revisions for radiographic and implant-related complications differ significantly in their overall 2-yr recovery compared to NR, using a normalized integrated health state method. Traditional methods for analyzing revision patients' recovery kinetics may overlook delayed improvements.

Co-modulation of stimulus rate and current from elevated baselines expands head motion encoding range of the vestibular prosthesis.

An implantable prosthesis that stimulates vestibular nerve branches to restore sensation of head rotation and vision-stabilizing reflexes could benefit individuals disabled by bilateral loss of vestibular sensation. The normal vestibular system encodes head movement by increasing or decreasing firing rate of the vestibular afferents about a baseline firing rate in proportion to head rotation velocity. Our multichannel vestibular prosthesis emulates this encoding scheme by modulating pulse rate and pulse current amplitude above and below a baseline stimulation rate (BSR) and a baseline stimulation current. Unilateral baseline prosthetic stimulation that mimics normal vestibular afferent baseline firing results in vestibulo-ocular reflex (VOR) eye responses with a wider range of eye velocity in response to stimuli modulated above baseline (excitatory) than below baseline (inhibitory). Stimulus modulation about higher than normal baselines resulted in increased range of inhibitory eye velocity, but decreased range of excitatory eye velocity. Simultaneous modulation of rate and current (co-modulation) above all tested baselines elicited a significantly wider range of excitatory eye velocity than rate or current modulation alone. Time constants associated with the recovery of VOR excitability following adaptation to elevated BSRs implicate synaptic vesicle depletion as a possible mechanism for the small range of excitatory eye velocity elicited by rate modulation alone. These findings can be used toward selecting optimal baseline levels for vestibular stimulation that would result in large inhibitory eye responses while maintaining a wide range of excitatory eye velocity via co-modulation.

Control of a neuroprosthesis for grasping using off-line classification of electrocorticographic signals: case study.

STUDY DESIGN: Proof of concept study to control a neuroprosthesis for grasping using identification of arm movements from ECoG signals. OBJECTIVE: To test the feasibility of using electrocorticographic (ECoG) signals as a control method for a neuroprosthesis for grasping. SETTING: Acute care hospital, Toronto Western Hospital and spinal cord injury (SCI) rehabilitation centre, Toronto Rehabilitation Institute, Lyndhurst Centre. Both hospitals are located in Toronto, Canada. METHODS: Two subjects participated in this study. The first subject had subdural electrodes implanted on the motor cortex for the treatment of essential tremor (ET). ECoG signals were recorded while the subject performed specific arm movements. The second subject had a complete SCI at C6 level (ASIA B score) and was fitted with a neuroprosthesis, capable of identifying arm movements from ECoG signals off-line, for grasping. To operate the neuroprosthesis, subject 2 issued a command that would trigger the release of a randomly selected ECoG signal recorded from subject 1, associated with a particular arm movement. The neuroprosthesis identified which arm movement was performed at the time of recording and used that information to trigger the stimulation sequence. A correct ECoG classification resulted in the neuroprosthesis producing the correct hand function (that is grasp and release). RESULTS: The neuroprosthesis classified ECoG signals correctly delivering the correct stimulation strategy with 94.5% accuracy. CONCLUSIONS: The feasibility of using ECoG signals as a control strategy for a neuroprosthesis for grasping was shown.

[Artificial sight: recent developments]. / Künstliches Sehen: Stand der Entwicklung.

The implantation of electronic retina stimulators appears to be a future possibility to restore vision, at least partially in patients with retinal degeneration. The idea of such visual prostheses is not new but due to the general technical progress it has become more likely that a functioning implant will be on the market soon. Visual prosthesis may be integrated in the visual system in various places. Thus there are subretinal and epiretinal implants, as well as implants that are connected directly to the optic nerve or the visual cortex. The epiretinal approach is the most promising at the moment, but the problem of appropriate modulation of the image information is unsolved so far. This will be necessary to provide a interpretable visual information to the brain. The present article summarises the concepts and includes some latest information from recent conferences.

Visual prosthetics 2006: assessment and expectations.

This report provides a brief overview of blinding eye diseases for which prosthetic vision may hold promise as a treatment modality, and of current and near-term technological approaches towards the creation of prosthetic interfaces with the remaining visual system. Principal anatomical, physiological, technological and functional obstacles and possible solutions are outlined, and references are provided to pioneering work by over a dozen groups on four continents.

Evaluation of extraocular electrodes for a retinal prosthesis using evoked potentials in cat visual cortex.

OBJECTIVE: To assess the efficacy of a device using extraocular electrodes as a retinal prosthesis by evaluating the responses evoked in the visual cortex to electrical stimulation. METHODS: In anaesthetised cats, a lateral orbital dissection and ipsilateral parietal craniotomy was performed. Two extraocular retinal prosthesis (ERP) disc electrodes were sutured to the sclera on the lateral and superior aspects of the globe. Retinal stimulation was performed with charge-balanced constant-current pulses. Potentials evoked in the visual cortex were measured with a ball electrode placed on the lateral gyrus after removal of the dura. RESULTS: Stable attachment of the ERP electrodes to the globe was achieved with scleral sutures. Visual cortex responses were recorded with the electrodes in bipolar and monopolar configurations. The evoked response consisted of an early component with a peak around 8 ms, and a late component with a peak after 50 ms. Thresholds for evoking a response occurred at current intensities as low as 500 microA. Through extrapolation from evoked response amplitude data, thresholds as low as 300 microA were calculated. Cathodal monopolar stimulation demonstrated lower thresholds than anodal stimulation for evoking cortical responses. CONCLUSIONS: The ERP electrodes can be easily attached to the globe and are effective in electrically stimulating the retina, evoking responses in the primary visual cortex. Threshold charge-density was within safe limits for neural stimulation.

Transcutaneous functional electrical stimulation for grasping in subjects with cervical spinal cord injury.

STUDY DESIGN: Case series. OBJECTIVES: To evaluate the benefit, shortcomings and acceptance of a new transcutaneous functional electrical stimulation (FES) technology aimed at improving the grasp function in tetraplegic subjects in acute and postacute rehabilitation. SETTING: Spinal cord injury (SCI) centre, university hospital. METHODS: : Subjects (N=11) with complete or incomplete SCI at C4/5-C7 who started FES 1-67 months after their accident were included. Hand function tests, analysis of video recordings and of written documentation of FES sessions, status of muscle strength, and follow-up query were used as outcome measures. RESULTS: Nine subjects used FES as a neuroprosthesis. Eight demonstrated improved grasp function and performance in activities of daily living. In one subject, no benefit from FES was observed. Two other subjects showed improvements in muscle strength and facilitation of active movement with FES. Four subjects successfully integrated FES as neuroprosthesis in everyday life within the rehabilitation centre. Three received the system for home use. The most relevant reasons for stopping the FES application were: (i) improvement of voluntary grasp function, (ii) physical and psychological problems, (iii) no available stimulator for home use, and (iv) insufficient assistance for electrode placement at home. Shortcomings related to the transcutaneous surface technology (eg pain or coactivation of neighbouring muscles) could usually be reduced, or did not limit the efficiency or acceptance of FES. Individually designed digital or analogue control devices were preferred. CONCLUSION: Tetraplegic subjects in acute and postacute rehabilitation can profit from a new transcutaneous FES system with respect to functional use and independence. It can be implemented in the rehabilitation programme for muscle strengthening and facilitation of voluntary activity. For a successful application of FES, there is a need for individual electrode placement, stimulation programmes, and FES control devices.

Neural prostheses for vision: designing a functional interface with retinal neurons.

A number of prevalent eye diseases exist which may lead to partial or total blindness, and for which there are currently no cures or means by which to restore lost sight. Based on recent progress, it has become apparent that artificial prosthetic devices, which would use electrical stimulation of neurons in the visual pathway to elicit visual percepts, are likely to some day become a viable treatment for patients blinded by these diseases. A number of recent scientific reviews have summarized general functional electrical stimulation (FES) approaches related to the visual system, and many of the technical considerations regarding fabrication, biocompatibility, stimulation thresholds and electrotoxicity. This review will address a principal outstanding question in retinal prosthesis development: the design and implementation of a functional interface with the retina. A functional interface between electrodes and retinal neurons will be stable, biocompatible, and will convey useful information to the visual system. Several parameters related to both the artificial and biological aspects of the interface must be considered; this paper will emphasize electrode design. Additional issues central to the development of prosthesis interface design, including retinal physiology, eye diseases, and existing animal models of retinal degeneration, are also summarized.

Neuroprostheses to treat neurogenic bladder dysfunction: current status and future perspectives.

BACKGROUND: Neural prostheses are a technology that uses electrical activation of the nervous system to restore function to individuals with neurological or sensory impairment. INTRODUCTION: This article provides an introduction to neural prostheses and lists the most successful neural prostheses (in terms of implanted devices). CURRENT TREATMENT: The article then focuses on neurogenic bladder dysfunction and describes two clinically available implantable neural prostheses for treatment of neurogenic bladder dysfunction. Special attention is given to the usage of these neural prostheses in children. FUTURE TREATMENT: Finally, three new developments that may lead to a new generation of implantable neural prostheses for bladder control are described. They may improve the neural prostheses currently available and expand further the population of patients who can benefit from a neural prosthesis.

Dose-dependent effects of combined IGF-I and TGF-beta1 application in a sheep cervical spine fusion model.

Combined IGF-I and TGF-beta1 application by a poly-(D,L-lactide) (PDLLA) coated interbody cage has proven to promote spine fusion. The purpose of this study was to determine whether there is a dose-dependent effect of combined IGF-I and TGF-beta1 application on intervertebral bone matrix formation in a sheep cervical spine fusion model. Thirty-two sheep underwent C3/4 discectomy and fusion. Stabilisation was performed using a titanium cage coated with a PDLLA carrier including no growth factors in group 1 ( n=8), 75 micro g IGF-I plus 15 micro g TGF-beta1 in group 2 ( n=8), 150 micro g IGF-I plus 30 micro g TGF-beta1 in group 3 ( n=8) and 300 micro g IGF-I plus 60 micro g TGF-beta1 in group 4 ( n=8). Blood samples, body weight and temperature were analysed. Radiographic scans were performed pre- and postoperatively and after 1, 2, 4, 8, and 12 weeks. At the same time points, disc space height and intervertebral angle were measured. After 12 weeks, the animals were killed and fusion sites were evaluated using quantitative computed tomographic (CT) scans to assess bone mineral density, bone mineral content and bony callus volume. Biomechanical testing was performed and range of motion, and neutral and elastic zones were determined. Histomorphological and histomorphometrical analysis were carried out and polychrome sequential labelling was used to determine the time frame of new bone formation. In comparison to the group without growth factors (group 1), the medium- and high-dose growth factor groups (groups 3 and 4) demonstrated a significantly higher bony callus volume on CT scans, a higher biomechanical stability, an advanced interbody bone matrix formation in histomorphometrical analysis, and an earlier bone matrix formation on fluorochrome sequence labelling. Additionally, the medium- and high-dose growth factor groups (groups 3 and 4) demonstrated a significantly higher bony callus volume, a higher biomechanical stability in rotation, and an advanced interbody bone matrix formation in comparison to the low-dose growth factor group (group 2). No significant difference could be determined between the medium- and the high-dose growth factor groups (groups 3 and 4, respectively). The local application of IGF-I and TGF-beta1 by a PDLLA-coated cage significantly improved results of interbody bone matrix formation in a dose-dependent manner. The best dose-response relationship was achieved with the medium growth factor dose (150 micro g IGF-I and 30 micro g TGF-beta1). With an increasing dose of these growth factors, no further stimulation of bone matrix formation was observed. Although these results are encouraging, safety issues of combined IGF-I and TGF-beta1 application for spinal fusion still have to be addressed.

The functional impact of the Freehand System on tetraplegic hand function. Clinical Results.

STUDY DESIGN: A B design with subjects acting as their own control when the device is turned off. OBJECTIVE: Evaluation of the efficacy of the NeuroControl Freehand System. SETTING: A supra regional spinal unit in the UK. METHODS: The Freehand system is an implanted Functional Electrical Stimulation (FES) device for restoration of lateral and palmar grasps following C5 or C6 tetraplegia. Its use was assessed using the Grasp Relies Test (GRT), Activities of Daily Living (ADL), Grip strength and two-point discrimination. RESULTS: Seven out of nine subjects are currently daily users of the device. There were statistically significant increases in the number of types of task achieved and the number of repetitions of those tasks in the Grasp Release Test. The system produced a functionally strong grasp where no grip strength at all was possible prior to implantation. Three of the four subjects who had sensory ability prior to implant showed improvements in two-point discrimination. Most of the selected tasks were achieved in the ADL assessment indicating a significant improvement in independence. CONCLUSION: The Freehand system can significantly improve the functional ability of C5 and C6 lesion tetraplegics. SPONSORSHIP: This study was funded by the charity INSPIRE.

Electrical stimulation for the treatment of bladder dysfunction: current status and future possibilities.

Electrical stimulation of peripheral nerves can be used to cause muscle contraction, to activate reflexes, and to modulate some functions of the central nervous system (neuromodulation). If applied to the spinal cord or nerves controlling the lower urinary tract, electrical stimulation can produce bladder or sphincter contraction, produce micturition, and can be applied as a medical treatment in cases of incontinence and urinary retention. This article first reviews the history of electrical stimulation applied for treatment of bladder dysfunction and then focuses on the implantable Finetech-Brindley stimulator to produce bladder emptying, and on external and implantable neuromodulation systems for treatment of incontinence. We conclude by summarizing some recent research efforts including: (a) combined sacral posterior and anterior sacral root stimulator implant (SPARSI), (b) selective stimulation of nerve fibers for selective detrusor activation by sacral ventral root stimulation, (c) microstimulation of the spinal cord, and (d) a newly proposed closed-loop bladder neuroprosthesis to treat incontinence caused by bladder overactivity.

Developing prosthetics to treat cognitive disabilities resulting from acquired brain injuries.

Persistent cognitive disabilities represent the most troublesome consequences of acquired brain injury. Although these problems are widely recognized, few neuroprosthetic efforts have focused on developing therapeutic strategies aimed at improving general cognitive functions such as sustained attention, intention, working memory or awareness. If possible, effective modulation of these neuropsychologic components might improve recovery of interactive behaviors. The emerging field of neuromodulation holds promise that technologies developed to treat other neurological disorders may be adapted to address the cognitive problems of patients suffering from acquired brain injuries. We here discuss initial efforts at neuromodulation in patients in the persistent vegetative state and aspects of recent studies of the underlying neurobiology of PVS and other severe brain injuries. Innovative strategies for open-loop and closed-loop neuromodulation of impaired cognitive function are outlined. We discuss the possibilities of linking neuromodulation techniques to underlying neuronal mechanisms underpinning cognitive rehabilitation maneuvers. Ethical considerations surrounding the development of these strategies are reviewed.