Multivariate Analysis of Risk Factors for Complications in Pediatric Tissue Expansion.

BACKGROUND: Tissue expanders represent one of the main surgical options for skin reconstruction in cases of tumors, traumalike burn injury, scar contracture, and alopecia. However, the tissue expander device is also associated with complications such as infection and extrusion. The aim of this study was to analyze risk factors for major complications of use of tissue expanders in pediatric patients using multivariate analysis. METHODS: A retrospective, single-center observational study was performed over 10 years in pediatric patients who were treated with tissue expanders for tumors, nevus, scars, burn reconstruction, and alopecia from April 2012 to March 2022. The primary outcome was overall complications per operation and expander, including infection and extrusion. Ten predictor variables were included as risk factors based on previous studies and as new factors considered important from clinical experience. Univariate and multivariate logistic regression analyses were performed to identify risk factors for major complications such as expander infection or extrusion. RESULTS: The study included 44 patients who underwent 92 operations using 238 tissue expanders. The overall complication rate per expander was 14.3%. Univariate logistic regression analysis identified associations of younger age, number of expanders used per operation, history of infection, and tissue expander locations with a higher complication rate. In multivariate logistic regression analysis, younger age (odds ratio, 1.14; P = 0.043) was associated with a high likelihood of expander complications. CONCLUSIONS: Younger age is an independent risk factor for tissue expander complications in pediatric patients. This factor should be considered in preoperative planning and discussions with the patient's family.

Air Versus Saline in Tissue Expanders: A Systematic Review of the Literature.

BACKGROUND: There has been a greater focus in recent literature proposing air to be a superior medium to saline in tissue expanders. This study aims to review the literature and assess the quality of data on the efficacy and safety of air as an alternative medium to saline in tissue expanders, in the setting of postmastectomy two-stage reconstruction. METHODS: A systematic review regarding air inflation of tissue expanders was conducted using PubMed, Embase, Cochrane Library, and Web of Science. The methods followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Three reviewers separately performed data extraction and comprehensive synthesis. RESULTS: A total of 427 articles were identified in our search query, of which 11 met the inclusion criteria. Three pertained to inflation with room air, and eight pertained to inflation with CO2 using the AeroForm device. They were comparable to decreased overall complication rates in the room air/CO2 cohort compared to saline, although statistical significance was only observed in one of five two-arm studies. Investigating specific complications in the five two-arm studies, significantly lower rates of skin flap necrosis were only observed in two CO2-based studies. Studies rarely discussed other safety profile concerns, such as the impacts of air travel, radiation planning, and air extravasation beyond descriptions of select patients within the cohort. CONCLUSION: There is insufficient evidence to suggest improved outcomes with room air inflation of tissue expanders. Further work is needed to fully characterize the benefits and safety profiles of air insufflation before being adopted into clinical practice.

Post-mastectomy Breast Reconstruction With Gas vs Saline Tissue Expanders: Does the Fill Type Matter?

The most common reconstruction technique following mastectomy is a 2-stage technique that involves tissue expansion followed by definitive implant-based reconstruction (IBR). Tissue expanders (TEs) have classically used saline for initial fill; however, TEs with an initial gas fill (GTE)-including the CO2-based AeroForm (AirXpanders, San Francisco, CA) TE and TEs initially filled with atmospheric air-have been increasingly used in the past decade. We aimed to compare the outcomes in breast reconstruction for tissue expanders initially filled with saline vs gas. PubMed was queried for studies comparing gas- and saline-filled tissue expanders (STEs) used in IBR. A meta-analysis was performed on major postoperative outcomes and the required expansion and definitive reconstruction time. Eleven studies were selected and included in the analysis. No significant differences existed between tissue expansion with GTEs vs STEs for 11 of the 13 postoperative outcomes investigated. Out of the complications investigated, only the risk of infection/cellulitis/abscess formation was significantly lower in the GTE cohort (odds ratio 0.62; 95% CI, 0.47 to 0.82; P = .0009). The time to definitive reconstruction was also significantly lower in the GTE cohort (mean difference [MD], 45.85 days; 95% CI, -57.80 to -33.90; P < .00001). The total time to full expansion approached significance in the GTE cohort (MD, -20.33 days; 95% CI, -41.71 to 1.04; P = .06). A cost analysis considering TE cost and infection risk determined that GTE use saved a predicted $2055.34 in overall healthcare costs. Surgical outcomes for both fill types were predominantly similar; however, GTEs were associated with a significantly decreased risk of postoperative infection compared to saline-filled TEs. GTEs could also reduce healthcare expenditures and require less time until definitive reconstruction after placement.

Surgical management of pediatric renovascular hypertension and midaortic syndrome at a single-center multidisciplinary program.

OBJECTIVE: To evaluate the outcomes of various surgical approaches in the treatment of renovascular hypertension and midaortic syndrome (MAS) in children. METHODS: We performed a retrospective medical record review of patients who had undergone surgery for renovascular hypertension from 2010 to 2018 at our center under the care of a multidisciplinary team. The operative interventions included mesenteric artery growth improves circulation (MAGIC), tissue expander-stimulated lengthening of arteries (TESLA), aortic bypass using polytetrafluorethylene, renal artery reimplantation, and autotransplantation. The MAGIC procedure uses the meandering mesenteric artery as a free conduit for aortic bypass. The TESLA procedure is based on lengthening the normal distal aorta and iliac arteries by gradual filling of a retroaortic tissue expander for several weeks, followed by resection of the stenotic aorta and subsequent primary reconstruction. RESULTS: A total of 39 patients were identified, 10 with isolated renal artery stenosis, 26 with MAS, and 3 with systemic inflammatory vasculitis. The median age at presentation and surgery was 6.4 years (range, 0-16.3 years) and 9.3 years (range, 0-9.2 years), respectively. The MAS-associated syndromes included neurofibromatosis type 1 (15.4%) and Williams syndrome (5.1%), although most cases were idiopathic. At surgery, 33.3% had had stage 1 hypertension (HTN), 53.8% stage 2 HTN, and 12.8% normal blood pressure with a median of three antihypertensive medications. Follow-up of 37 patients at a median of 2.5 years demonstrated normal blood pressure in 86.1%, stage 1 HTN in 8.3%, and stage 2 HTN in 5.6%, with a median of one antihypertensive medication for the entire cohort. CONCLUSIONS: The patterns of vascular involvement leading to renovascular hypertension in children are variable and complex, requiring thoughtful multidisciplinary planning and surgical decision-making. The MAGIC and TESLA procedures provide feasible approaches for aortic bypass and reconstruction using autologous tissues and will result in normalization of blood pressure in 85% of children 2.5 years after surgery.

Establishment of a Novel Mouse Model for Soft Tissue Expansion.

BACKGROUND: Despite its increasing use, not much is known about tissue expansion, and its complication rates are significantly high. Thus, there is an urgent need to establish a stable animal model to overcome the limitations and complications of tissue expansion. Although the mouse model has shown several advantages in the in-depth studies, an appropriate mouse expansion model has rarely been reported, likely because of its loose skin. MATERIALS AND METHODS: A micro expander was designed and implanted under the scalp of a mouse (expanded group); sterilized saline was regularly injected into the expander. In sham-operated mice (control group), a silicone sheet was implanted under the scalp. Skin samples were collected 5 wk after surgery. Histologic changes including epidermal and dermal thickness and collagen fiber arrangement were analyzed. In addition, vascular density and cell proliferation ratio were determined. An ultrastructural analysis was also performed. RESULTS: With the application of the expansion device, the skin became tight and showed area enlargement. The epidermal thickness of the expanded skin increased significantly (P < 0.01), whereas the thickness of the dermis decreased significantly (P < 0.05) as compared with the control skin. Masson staining demonstrated that collagen bundles were arranged more compactly in the expanded skin (P < 0.05) than in the controls. Furthermore, more proliferating cells (P < 0.05) and blood vessels (P < 0.01) were observed. Transmission electron microscopy showed that the fibers of expanded skin were stretched and broken into bundles of various diameters, with abundant active fibroblasts. CONCLUSIONS: A reliable mouse model of scalp skin expansion was successfully established, which may be a promising tool for in-depth studies on skin soft tissue expansion.

Direct-To-Implant and 2-Stage Breast Reconstruction After Nipple Sparing Mastectomy: Results of a Retrospective Comparison.

Breast reconstruction after nipple sparing mastectomy (NSM) plays, nowadays, a fundamental role in breast cancer management. There is no consensus on the best implant-based reconstruction technique, considering 2 stages (expander-prosthesis) or direct-to-implant (DTI). A retrospective review of consecutive adult female patients who underwent NSM with breast reconstruction over a 3-year period (January 2013 to December 2015) was performed. Patients were divided into 2 groups according to the type of reconstruction: expander/prosthesis (group A) and DTI (group B). Anamnestic data were collected. Number and type of procedures, complications and esthetic satisfaction were registered and compared. Fifty-six patients were included in group A (34.6%) and 106 in group B (65.4%). Complications associated with the 2 types of breast reconstruction were not different (P = 0.2). Patients in group A received a higher number of total surgical procedures (considering revisions, lipostructures and contralateral symmetrizations) than those in group B (2.5 ± 0.69 and 1.88 ± 1.02, P = 0.0001). Satisfaction with breast reconstruction resulted higher in group A (7.5 ± 2.6 and 6 ± 1.9, P = 0.0004). At the multivariate analysis, chemotherapy and radiotherapy were not correlated with complications, regardless of the group (odds ratio, 0.91 and 2.74, respectively). Radiotherapy and chemotherapy did not even influence the esthetic result, regardless of the group (P = 0.816 and P = 0.521, respectively). Prosthetic breast reconstructions, both in a single and in 2 stages, are welcomed by patients and have relatively low and almost equivalent complication rates, independent of other factors such as chemotherapy, radiotherapy, lymphadenectomy, smoking and age. In our experience, 2-stage breast reconstruction, although requiring more operations, is associated with a higher esthetic satisfaction. Patients who perform a DTI breast reconstruction after NSM should be informed of the high probability of surgical revision.

Treatment With Topical Deferoxamine Improves Cutaneous Vascularity and Tissue Pliability in an Irradiated Animal Model of Tissue Expander-Based Breast Reconstruction.

PURPOSE: Postmastectomy radiation therapy is an important component of the multimodality approach to later-stage breast cancers. Unfortunately, despite its proven survival benefits, postmastectomy radiation therapy is deleterious to the skin and soft tissue, causing increased complications and worse aesthetic outcomes after breast reconstruction.There is currently no effective pharmaceutical agent to mitigate the soft tissue fibrosis and hypovascularity associated with soft tissue radiation. We hypothesized that a novel topical formulation of deferoxamine (DFX) will result in improved cutaneous vascularity and soft tissue pliability in an animal model of irradiated tissue expander-based breast reconstruction. METHODS: This study consisted of 16 hairless rats divided into 4 equal groups: a control group (expander only), a tissue expanded and irradiated group, a tissue expanded + DFX group, and a tissue expanded/irradiated/DFX group. A novel topical formulation of DFX consisted of reconstituted drug dissolved in agents designed to enhance dermal penetrance. Vessels per high-power field (vHPF) were quantified histologically; micro-computed tomography angiography was used to assess vessel volume fraction (VVF) and vessel length density. RESULTS: Irradiated skin had less vascularity compared with control (3.81 vHPF vs 8.25 vHPF, P = 0.03; 0.79% VVF vs 1.53% VVF, P = 0.06). Treatment of irradiated skin with topical DFX reversed these effects, resulting in vascular findings similar to the control group histologically (7.94 vHPF vs 8.25 HPF, P = 0.985) and via micro-computed tomography angiography (1.05% VVF vs 1.53% VVF, P = 0.272). Similarly, radiation resulted in less volume expansion compared with controls (0.72 vs 0.8 mL, P = 0.04), whereas treatment with topical DFX reversed this effect, allowing for an expansion volume similar to the control group (0.81 vs 0.80 mL, P = 0.999). CONCLUSIONS: In an animal model of irradiated tissue expander-based breast reconstruction, treatment with topical DFX improved the cutaneous vascularity and tissue pliability, resulting in vascular density and final tissue expansion volumes similar to those found in the nonirradiated control group. Topical DFX may be an effective agent for the treatment of soft tissue radiation injury; future studies are indicated to further characterize this novel drug formulation.

[Advanced skull defect repair]. / Rekonstruktsiia obshirnogo kombinirovannogo defekta cherepa.

It is presented case report of successful repair of advanced combined defect of parietal-temporal-occipital scalp over one-half of skull vault with an excellent cosmetic result. To do this, the authors used a staged expander dermal tension, i.e. repeated stretching of the remaining scalp tissues combined with cranioplasty using mesh titanium implant.

Predictors of complications after direct-to-implant breast reconstruction with an acellular dermal matrix from a multicentre randomized clinical trial.

BACKGROUND: In the multicentre randomized trial BRIOS (Breast Reconstruction In One Stage), direct-to-implant (DTI) breast reconstruction with an acellular dermal matrix (ADM) was associated with a markedly higher postoperative complication rate compared with two-stage tissue expander/implant breast reconstruction. This study aimed to identify factors that contribute to the occurrence of complications after DTI ADM-assisted breast reconstruction. METHODS: Data were obtained from the BRIOS study, including all patients treated with DTI ADM-assisted breast reconstruction. Logistic regression analyses were performed to identify factors predictive of postoperative complications. RESULTS: Fifty-nine patients (91 breasts) were included, of whom 27 (35 breasts) developed a surgical complication. Reoperations were performed in 29 breasts (32 per cent), with prosthesis removal in 22 (24 per cent). In multivariable analyses, mastectomy weight was associated with complications (odds ratio (OR) 1·94, 95 per cent c.i. 1·33 to 2·83), reoperations (OR 1·70, 1·12 to 2·59) and removal of the implant (OR 1·55, 1·11 to 2·17). Younger patients (OR 1·07, 1·01 to 1·13) and those who received adjuvant chemotherapy (OR 4·83, 1·15 to 20·24) more frequently required reoperation. In univariable analyses, adjuvant radiotherapy showed a trend towards more complications (OR 7·23, 0·75 to 69·95) and removal of the implant (OR 5·12, 0·76 to 34·44), without reaching statistical significance. CONCLUSION: Breast size appeared to be the most significant predictor of complications in DTI ADM-assisted breast reconstruction. The technique should preferably be performed in patients with small to moderate sized breasts. Registration number: NTR5446 ( http://www.trialregister.nl).

Endoscopic Delayed Breast Reconstruction With Expanders and Implants via the Axillary Incision Made for Sentinel Lymph Node Biopsy or Lymphadenectomy.

BACKGROUND: Classic techniques of delayed prosthetic breast reconstruction use the mastectomy scar as an access route. As a result, the filling of the expander must be postponed until the wounds have healed. This creates an asymmetry between the breasts with the volume changes caused by the filling of the expander, which may occur over several weeks and cause considerable discomfort. METHODS: Delayed breast reconstruction was performed via the axillary incision made for sentinel lymph node biopsy or lymphadenectomy with endoscopic assistance and detachment of the pectoralis major muscle. The filling of the expander and symmetrization with the contralateral breast was performed in the first stage.The expander was replaced with the definitive prosthesis 3 months later, after endoscopic capsulotomy. Fat grafting was performed to create a lipobed around the implant and to improve tissue quality. RESULTS: Sixty-two patients underwent surgery. Mean follow-up was 19 months. There were no major complications in the reconstructed breast. One case of hematoma in a contralateral breast reduction and an oil cystic mass secondary to fat grafting were recorded. In all cases, the filling of the expander with the definitive volume was possible during the first stage. CONCLUSIONS: Endoscopic delayed breast reconstruction with insertion of implants through the axillary incision for sentinel node biopsy or lymphadenectomy is safe and feasible. It achieves complete intraoperative expansion, symmetry between the volumes of the breasts during the first stage, and avoids problems with the scar and the risk of extrusion, as the scar is placed remotely in the axilla.

Moffitt Cancer Center Experience of Tissue Expander Breast Reconstruction: Does Acellular Dermal Matrix Increase Return to the Operating Room?

BACKGROUND: Tissue expander and implant remains the most common technique for breast reconstruction. A controversial topic within this method is routine use of acellular dermal matrix (ADM). Acellular dermal matrices have increased risks of infection, seroma, hematoma, skin flap necrosis, and total complications. METHODS: After an institutional review board approval, a retrospective chart review was conducted of 756 tissue expander with implant cases from November 2010 to November 2016 at Moffitt Cancer Center with 2 breast reconstruction surgeons. Patients were grouped in 2 groups: tissue expander alone reconstruction (TE) and tissue expander with ADM (TE + ADM). Complications were defined by return visits to the operating room for irrigation and debridement as well as for subsequent tissue expander placement. RESULTS: There were 703 patients in the TE group and 53 in the TE + ADM group. Patients undergoing TE + ADM reconstruction were 3 times more likely to experience return to operating room compared with patients undergoing TE alone (7.5% vs 2.4%). Patients were significantly more likely to undergo 3 or more subsequent tissue expander placement procedures with TE + ADM (54.7%) compared with TE alone (4.8%) (P < 0.0001). CONCLUSIONS: Although ADM may be appropriate for specific patients, its use in tissue expander breast reconstruction should be judiciously selected, because there is an observed increase in complications needing return to the operating room.

Effects of the Metallic Port in Tissue Expanders on Dose Distribution in Postmastectomy Radiotherapy: A Tridimensional Experimental Model of Dosimetry in Breast Reconstruction.

The purpose of this research was to develop an experimental model of dosimetry using a breast phantom and evaluate the effects of the metallic port in tissue expanders on dose distribution in postmastectomy radiotherapy. Dose distribution was assessed using an experimental acrylic dosimetry simulator in the absence and presence of a metallic disc (MD), which is similar to that used in tissue expanders containing a magnetic port, by collecting coronal and sagittal radiochromic films. Dosimetry film analysis did not show any changes in dose distribution, except for a MD shadow in the sagittal film where the dose distribution rate was on average 14% lower than in other areas. This model very closely resembled actual breast reconstruction with a tissue expander containing a magnetic port. Scattering or attenuation of the irradiation dose due to interference of the MD was not evident in areas that could jeopardize the effectiveness of radiation therapy. Therefore, the presence of the MD inside the tissue expander does not likely have an impact on radiotherapy effectiveness during immediate breast reconstruction.

Primary Closure of Wide Fasciotomy and Surgical Wounds Using Rubber Band-Assisted External Tissue Expansion: A Simple, Safe, and Cost-effective Technique.

BACKGROUND: Although decompressive fasciotomy is a limb-saving procedure in the setting of acute compartment syndrome, it leaves a large wound defect with tissue edema and skin retraction that can preclude primary closure. Numerous techniques have been described to address the challenge of closing fasciotomy wounds. This study reports our experience with fasciotomy closure using rubber bands (RBs) for external tissue expansion. METHODS: Patients were informed about RB closure and split-thickness skin graft options. Only patients who opted for RB closure and had wounds that could not be approximated using the pinch test underwent the procedure. Starting from the apex and progressively advancing, the RBs were applied to the skin edges at 3 to 4 mm intervals using staples. The RBs were advanced by twisting back-and-forth to create a criss-cross pattern. One week after application, fasciotomy wounds were closed primarily or underwent further RB application, based on clinical assessment of adequacy of skin advancement, compartment tension, and perfusion. Review of a prospectively maintained database was performed, including demographics, comorbidities, etiology, wound and operative details, hospital stay, and complications. RESULTS: Seventeen consecutive patients with 25 wounds (22 fasciotomy and 3 other surgical wounds) were treated using the RB technique. Average wound length and width measured 15.7 cm (range, 5-32 cm) and 5.2 cm (range, 1-12 cm), respectively. Locations of wounds included forearm (n = 12, 48.0%), leg (n = 7, 28.0%), hand (n = 4, 16.0%), elbow (n = 1, 4.0%), and hip (n = 1, 4.0%). Eighteen of 25 wounds (72.0%) were closed primarily after 1 RB application. Additional RB application was required for 5 wounds to achieve primary closure. Between stages, patients were discharged home if they did not have other conditions requiring in-hospital stay. No complications were observed, and no revision surgeries were required. Patient satisfaction was 100%, and all indicated that they would choose the RB technique over skin grafting. CONCLUSIONS: The modified RB technique is a simple, safe, and cost-effective alternative for treating fasciotomy and other surgical defects resulting in high patient satisfaction and good cosmetic outcome, without the need for split-thickness skin graft or flap coverage.

Complications After Total Skin-Sparing Mastectomy and Expander-Implant Reconstruction: Effects of Radiation Therapy on the Stages of Reconstruction.

BACKGROUND: Many patients undergoing total-skin sparing mastectomy (TSSM) and 2-staged expander-implant (TE-I) reconstruction require postmastectomy radiation therapy (PMRT). Additionally, many patients undergoing TSSM for recurrent cancer have a history of lumpectomy and radiation therapy (XRT). Few studies have looked at the impact of XRT on the stages of TE-I reconstruction. METHODS: Patients undergoing TSSM and immediate TE-I reconstruction between 2006 and 2013 were identified from a prospectively maintained database. Rates of TE-I loss and severe infection requiring intravenous antibiotics were compared in patients with prior XRT (85 cases) and PMRT (133 cases). Complications were divided by stage of reconstruction: first stage (TSSM and TE placement) and second stage (TE-I exchange). RESULTS: Mean follow-up time was 2.5 years. Patients with prior XRT had more complications after the first stage of reconstruction than the second (TE-I loss: 15% vs 5%, P = 0.03; infection: 20% vs 8%, P = 0.04). Patients receiving PMRT had low complication rates after the first stage, when they had not yet received radiation (TE-I loss: 2%; infection: 5%). However, complication rates after TE-I exchange (TE-I loss, 18%; infection, 31%) were significantly higher, and nearly 4-fold higher than patients with prior XRT. CONCLUSIONS: Patients with prior XRT are at high risk for complications after the first stage of TE-I reconstruction after TSSM; however, the risk of complications at the second stage is comparable to patients without radiation exposure and significantly lower than patients receiving PMRT. Patients receiving radiation therapy should be given appropriate preoperative counseling regarding their risks.

Direct-to-Implant as a Frontline Option for Immediate Breast Reconstruction: A Comparative Study With 2-Stage Reconstruction.

BACKGROUND: Immediate single-stage direct-to-implant breast reconstruction requires caution owing to the possibility of skin necrosis and implant failure. Nevertheless, this method has been performed widely for breast reconstruction. This study aimed to analyze the safety of single-stage implant reconstruction by comparing it with 2-stage reconstruction (TSR). METHODS: Immediate single-stage reconstructions (SSRs) and TSRs with a tissue expander, performed from January 2011 to December 2016, were retrospectively reviewed. Acellular dermal matrix was used in both groups to maintain similar pocket conditions. Risk factors were not considered in patient selection. RESULTS: We enrolled 290 patients including 8 who received bilateral breast reconstruction. A total of 298 breasts were operated, including 233 SSR cases (78%) and 65 TSR cases (22%). The surgical success (ie, the implant was maintained without explantation) rate was higher in SSR (97%) than in TSR (90.2%) (P = 0.03). Two-stage reconstruction had a significantly higher rate of hematoma (12.3% vs 3.4%, P = 0.005), seroma (41.5% vs 20.6%, P = 0.001), and implant failure (9.8% vs 3.0%, P = 0.03). However, the rate of skin necrosis was lower in TSR (7.7% vs 10.3%) with a trend toward significance (P = 0.053). The implant salvage rate was higher in SSR (61.1%) than in TSR (12.5%) even after revision operation (P = 0.013). CONCLUSIONS: Single-stage reconstruction yielded a lower complication rate than TSR. Moreover, the high salvage rate of SSR causes less concern about implant failure despite the possibility of revision operation. Therefore, SSR may be considered a frontline method for breast reconstruction without any patient selection interference.

Modified Activation Technique for Nasal Stent of Nasoalveolar Molding Appliance for Columellar Lengthening in Bilateral Cleft Lip/Palate.

Bilateral cleft lip/cleft palate is associated with nasal deformities typified by a short columella. The presurgical nasoalveolar molding (NAM) therapy approach includes reduction of the size of the intraoral alveolar cleft as well as positioning of the surrounding deformed soft tissues and cartilages. In a bilateral cleft patient, NAM, along with columellar elongation, eliminates the need for columellar lengthening surgery. Thus the frequent surgical intervention to achieve the desired esthetic results can be avoided. This article proposes a modified activation technique of the nasal stent for a NAM appliance for columellar lengthening in bilateral cleft lip/palate patients. The design highlights relining of the columellar portion of the nasal stent and the wire-bending of the nasal stent to achieve desirable results within the limited span of plasticity of the nasal cartilages. With this technique the vertical taping of the premaxilla to the oral plate can be avoided.

Radiation and depression associated with complications of tissue expander reconstruction.

PURPOSE: Rates of implant failure, wound healing delay, and infection are higher in patients having radiation therapy (RT) after tissue expander (TE) and permanent implant reconstruction. We investigated pretreatment risk factors for TE implant complications. PATIENTS AND METHODS: 127 breast cancer patients had TE reconstruction and radiation. For 85 cases of bilateral TE reconstruction, the non-irradiated breast provided an internal control. Comparison of differences in means for continuous variables used analysis of variance, then multiple pairwise comparisons with Bonferroni correction of p value. RESULTS: Mean age was 53 ± 10.1 years with 14.6% African-American. Twelve (9.4%) were BRCA positive (9 BRCA1, 4 BRCA2, 1 Both). Complications were: Grade 0 (no complication; 43.9%), Grade 1 (tightness and/or drifting of implant or Baker Grade II capsular contracture; 30.9%), Grade 2 (infection, hypertrophic scarring, or incisional necrosis; 9.8%), Grade 3 (Baker Grade III capsular contracture, wound dehiscence, or impending exposure of implant; 5.7%), Grade 4 (implant failure, exchange of implant, or Baker Grade IV capsular contracture; 9.8%). 15.3% (19 cases) experienced Grade 3 or 4 complication and 9.8% (12 cases) had Grade 4 complication. Considering non-irradiated breasts, there were two (1.6%) Grade 3-4 complications. For BMI, there was no significant difference by category as defined by the CDC (p = 0.91). Patients with depression were more likely to experience Grade 3 or 4 complication (29.4 vs 13.2%; p = 0.01). Using multiple logistic regression to predict the probability of a Grade 3 or 4 complications in patients with depression were found to be 4.2 times more likely to have a Grade 3 or 4 complication (OR = 4.2, p = 0.03). CONCLUSIONS: Higher rates of TE reconstruction complications are expected in patients receiving radiotherapy. An unexpected finding was that patients reporting medical history of depression showed statistically significant increase in complication rates.

Feasibility and scalability of spring parameters in distraction enterogenesis in a murine model.

BACKGROUND: Distraction enterogenesis has been investigated as a novel treatment for short bowel syndrome (SBS). With variable intestinal sizes, it is critical to determine safe, translatable spring characteristics in differently sized animal models before clinical use. Nitinol springs have been shown to lengthen intestines in rats and pigs. Here, we show spring-mediated intestinal lengthening is scalable and feasible in a murine model. MATERIALS AND METHODS: A 10-mm nitinol spring was compressed to 3 mm and placed in a 5-mm intestinal segment isolated from continuity in mice. A noncompressed spring placed in a similar fashion served as a control. Spring parameters were proportionally extrapolated from previous spring parameters to accommodate the smaller size of murine intestines. After 2-3 wk, the intestinal segments were examined for size and histology. RESULTS: Experimental group with spring constants, k = 0.2-1.4 N/m, showed intestinal lengthening from 5.0 ± 0.6 mm to 9.5 ± 0.8 mm (P < 0.0001), whereas control segments lengthened from 5.3 ± 0.5 mm to 6.4 ± 1.0 mm (P < 0.02). Diameter increased similarly in both groups. Isolated segment perforation was noted when k ≥ 0.8 N/m. Histologically, lengthened segments had increased muscularis thickness and crypt depth in comparison to normal intestine. CONCLUSIONS: Nitinol springs with k ≤ 0.4 N/m can safely yield nearly 2-fold distraction enterogenesis in length and diameter in a scalable mouse model. Not only does this study derive the safe ranges and translatable spring characteristics in a scalable murine model for patients with short bowel syndrome, it also demonstrates the feasibility of spring-mediated intestinal lengthening in a mouse, which can be used to study underlying mechanisms in the future.

A meta-analysis of implant-based breast reconstruction and timing of adjuvant radiation therapy.

BACKGROUND: Implant-based breast reconstruction is the most common type of reconstruction after postmastectomy radiation therapy (PMRT). The impact of the timing of PMRT to a tissue expander or permanent implant is not well understood. The purpose of this systematic review was to evaluate outcomes in implant-based reconstruction and the timing of PMRT. METHODS: A review of the English literature in the PubMed/MEDLINE database (2000-2016) was performed to identify all articles on implant-based breast reconstruction and PMRT. Cases from each study were grouped by PMRT to a tissue expander or PMRT to a permanent implant. Outcomes of interest included reconstructive failure and capsular contracture as overall rates and associations were pooled. Effect sizes (z values), risk ratios (RRs), and heterogeneity scores (I2) were calculated on meta-analysis. RESULTS: There were 20 studies meeting inclusion criteria with 2348 patients identified. Pooled analysis revealed an overall rate of reconstructive failure of 17.6% and Baker grade III/IV capsular contracture of 37.5%. PMRT applied to tissue expanders resulted in higher rates of reconstructive failure compared with PMRT applied to permanent silicone implants (20% versus 13.4%, RR = 2.33, P = 0.0083, 95% confidence interval 1.24-4.35), but lower rates of capsular contracture (24.5% versus 49.4%, RR = 0.53, P = 0.083, 95% confidence interval 0.26-1.09). CONCLUSIONS: Regardless of timing, PMRT applied to implant-based breast reconstruction was associated with high risk of reconstructive failure and capsular contracture. Surgeons should consider alternative strategies, such as autologous tissue reconstructions, in patients requiring PMRT.