Naikhoba C.O. Munabi

The ability of intra-operative perfusion mapping with laser-assisted indocyanine green angiography to predict mastectomy flap necrosis in breast reconstruction: A prospective trial

Mastectomy skin flap ischaemia leading to necrosis is a common occurrence. Laser-assisted indocyanine green (ICG) angiography can assist to locate these poorly perfused areas intra-operatively. Our study aims to identify specific perfusion values produced by ICG angiography that accurately predict mastectomy flap necrosis. A total of 42 patients undergoing autologous or implant-based breast reconstruction had mastectomy flaps imaged using laser-assisted ICG angiography at the completion of reconstruction. Intra-operative perfusion values were correlated with postoperative skin flap outcomes. Risk factors for abnormal perfusion were recorded and analysed. A total of 62 breast reconstructions were imaged, including 48 tissue expander reconstructions, six transverse rectus abdominis myocutaneous (TRAM) flaps, six deep inferior epigastric perforator (DIEP) flaps and two direct-to-implant reconstructions. Eight cases (13%) of full-thickness skin necrosis were identified postoperatively. A SPY Elite(®) value of ≤ 7 accurately predicted the development of flap necrosis at 88% sensitivity and 83% specificity. False-positive cases (those with perfusion values ≤ 7 which did not develop necrosis) were more likely to have a smoking history and/or to have had an epinephrine-containing tumescent solution used during mastectomy. Excluding patients with smoking or epinephrine use, a SPY value of ≤ 7 predicted flap necrosis with a sensitivity of 83% and specificity of 97%. Thus, these data suggest that laser-assisted ICG angiography predicts postoperative outcomes with high accuracy. In our series, a SPY value of ≤ 7 correlated well with mastectomy flap necrosis. Furthermore, smoking and intra-operative injections containing epinephrine should be considered when evaluating low perfusion values as they can lead to false-positive test results.

The Association between Smoking and Plastic Surgery Outcomes in 40,465 Patients: An Analysis of the American College of Surgeons National Surgical Quality Improvement Program Data Sets

Background: Smoking is known to negatively impact postoperative wound healing and increase infection risk. However, few studies have investigated whether the negative effects of smoking are similar for different procedures. The authors examined the association between smoking and postoperative outcomes for a diverse range of plastic surgery procedures. Methods: Using the American College of Surgeons National Surgical Quality Improvement Program data set, demographics and outcomes were examined for patients who underwent plastic surgery between 2007 and 2012. Multivariable logistic regression models assessed the relationship between smoking status and a range of postoperative outcomes, including medical and surgical complications and impaired wound healing. Patients were also evaluated for length of inpatient hospitalization while controlling for multiple demographic factors and type of procedure. Results: Forty thousand four hundred sixty-five patients were identified from the data set, including patients who had undergone breast, upper and lower extremity, abdominal, and craniofacial procedures. Current smokers constituted 15.7 percent of the cohort. Smokers had a higher likelihood of surgical (OR, 1.37; p < 0.0001) and medical complications (OR, 1.24; p = 0.0323) and increased odds for wound complications (OR, 1.49; p < 0.0001) and wound dehiscence (OR, 1.84; p < 0.0001). Smokers were also found to have increased odds of these complications even when subgroup analysis was performed according to major Current Procedural Terminology categories. Smoking also increased the odds of superficial wound infections (OR, 1.40; p < 0.0001). No difference was observed in hospital length of stay between smokers and nonsmokers. Conclusions: Smoking increases a multitude of postoperative complications after plastic surgery procedures. The effects of smoking on plastic surgery outcomes should be used to guide patients in preoperative smoking cessation and to evaluate protocols for managing patients who smoke. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.

The Role of Intraoperative Perfusion Assessment: What Is the Current State and How Can I Use It in My Practice?

Summary: Evolving intraoperative technology has an increased presence and usefulness in aiding surgeon clinical judgment. Many surgical devices are readily available as an adjunct to this gold standard assessment of adequate tissue perfusion. Intraoperative perfusion monitoring provides surgeons with the ability to interpret additional information that enhances surgical decision-making in real-time. Technologies include various dye-based and non–dye-based near-infrared angiography, tissue oximetry measurements, and ultrasound-based tools. This review summarizes the available intraoperative technologies for planning and assessment of tissue perfusion in plastic and reconstructive surgery. The authors discuss the available literature for the individual devices and supporting evidence for their use. The authors recommend the evidence-based use of these tools in indicated surgical cases to improve clinical outcomes.

Topical cilostazol inhibits neointimal hyperplasia in a rat interposition vein graft model.

Background: Neointimal hyperplasia is a common cause of vein graft failure resulting from luminal narrowing and occlusion. Cilostazol is a U.S. Food and Drug Administration–approved phosphodiesterase III and platelet aggregation inhibitor commonly used in peripheral vascular disease. The authors studied whether topical cilostazol treatment at the time of vein grafting helps limit the development of neointimal hyperplasia in a rat model. Methods: Six experimental rats and six control rats underwent interposition vein grafting into the femoral artery, followed by a single topical dose of cilostazol applied around the vein graft in the experimental animals. After 4 weeks, grafts were harvested and underwent histologic staining of axial sections to visualize intima thickness and elastin/myocyte content. Quantification was performed to assess total intima area. The intima-to-media and the intima-to–sum of intima and media ratios were determined to control for discrepancies in overall graft size. Results: Cilostazol-treated grafts had a thinner intima layer with less myocyte content compared with control grafts, amounting to an 82 percent decrease in total intima area compared with controls. A similar trend was seen even after controlling for overall graft size, with 85 and 76 percent reductions seen in intima-to-media and intima-to–sum of intima and media ratios, respectively. Conclusions: A single intraoperative dose of cilostazol applied locally significantly reduced intima size and smooth muscle content in rat interposition vein grafts examined 4 weeks postoperatively. A topical dose of cilostazol at surgery may therefore be helpful in controlling neointimal hyperplasia and reducing the need for systemic medications to prolong vein graft patency.

NOTCH3 regulates stem-to-mural cell differentiation in infantile hemangioma

Infantile hemangioma (IH) is a vascular tumor that begins with rapid vascular proliferation shortly after birth, followed by vascular involution in early childhood. We have found that NOTCH3, a critical regulator of mural cell differentiation and maturation, is expressed in hemangioma stem cells (HemSCs), suggesting that NOTCH3 may function in HemSC-to-mural cell differentiation and pathological vessel stabilization. Here, we demonstrate that NOTCH3 is expressed in NG2+PDGFRβ+ perivascular HemSCs and CD31+GLUT1+ hemangioma endothelial cells (HemECs) in proliferating IHs and becomes mostly restricted to the αSMA+NG2loPDGFRβlo mural cells in involuting IHs. NOTCH3 knockdown in HemSCs inhibited in vitro mural cell differentiation and perturbed αSMA expression. In a mouse model of IH, NOTCH3 knockdown or systemic expression of the NOTCH3 inhibitor, NOTCH3 Decoy, significantly decreased IH blood flow, vessel caliber, and αSMA+ perivascular cell coverage. Thus, NOTCH3 is necessary for HemSC-to-mural cell differentiation, and adequate perivascular cell coverage of IH vessels is required for IH vessel stability.

Abstract: 2 Stage Approach to Autologous Breast Reconstruction Is Cost Effective and Improves Aesthetic Outcomes

INTRODUCTION: The nipple-sparing mastectomy (NSM) improves aesthetic results after breast reconstruction through preservation of the entire skin envelope, obviating the need for reconstruction of the nipple areola complex (NAC). NSM, however, is associated with a higher risk for occult pathology and skin necrosis, which can require resection and compromise the reconstructive outcome. In DIEP flap reconstruction; we utilize a 2-staged approach, which preserves “banked” skin during the initial reconstruction. After skin demarcation or final pathology of the NAC is revealed, a second minor procedure occurs to remove the banked skin or reconstruct the NAC if needed. This study was designed to identify how frequently the banked skin was utilized and the associated operative costs to determine if a staged approach to reconstruction is beneficial.

Abstract: The Association Between Smoking and Plastic Surgery Outcomes in 40,465 patients: An Analysis of the ACS-NSQIP Datasets

INTRODUCTION: In plastic surgery, studies in smokers showing impaired post-operative wound healing and increased infection rates focus predominantly on breast procedures.1–4 However, the effect of smoking on post-surgical outcomes may vary based on anatomic location and tissue type. Using the American College of Surgeons National Surgery Quality Improvement Program (ACS-NSQIP) datasets, we examined associations between smoking and post-operative complications after a wide range of plastic surgery procedures.

Abstract 2: NOTCH3 Regulates Mural Cell Differentiation of HemSCs.

PurPose: Infantile hemangiomas (IHs) are vascular hyperplasias with high flow and have been proposed to originate from hemangioma stem cells (HemSCs). Proper vessel maturation requires interactions between endothelial cells and their surrounding mural cells. IH pathology has been proposed to be partially due to defective mural cell function. Previous studies in our lab showed NOTCH3 inhibition in HemSC resulted in reduced blood flow in a murine IH model as detected by US Doppler. This correlated with reduced vessel diameter when compared to controls. Since Notch3 functions to regulate mural cell maturation, we determined if Notch3 has a role in mural cell differentiation of HemSCs.

Abstract 51: NOTCH3 Regulates Hemangioma Stem Cell Differentiation and Alters the Vascular Phenotype in an Infantile Hemangioma Murine Model

CONCLUSION: Transplantation of DRCC after ionizing radiation exposure proved to be the most effective rescue therapy against acute radiation syndrome, as confirmed by 100% of recipients’ survival and expedited recovery of the hematopoietic system without developing GVHD. Our novel approach of DRCC transplantation may act as a bridging therapy supporting hematopoietic recovery and ameliorating injuries in patients exposed to the harmful effects of radiation. 51 NOTCH3 Regulates Hemangioma Stem Cell Differentiation and Alters the Vascular Phenotype in an Infantile Hemangioma Murine Model

Abstract 70: Propranolol Effects on Hemangiomas are Mediated via Distinct Pathways.

BaCkground: Wnt signaling is a critical pathway regulating craniofacial development, where dysregulation leads to orofacial clefts. Intracellular trafficking and secretion of wnt ligands is chaperoned by wntless (wls). In human, the WLS gene is on the short arm of the chromosome 1 (1p31.3) and several deletions of this region associated with craniofacial malformations have been reported. We hypothesize that the wls gene functions to modulate wnt signaling important in morphogenesis of the craniofacial skeleton.