David J. Hunter-Smith

Emerging Applications of Bedside 3D Printing in Plastic Surgery

Modern imaging techniques are an essential component of preoperative planning in plastic and reconstructive surgery. However, conventional modalities, including three-dimensional (3D) reconstructions, are limited by their representation on 2D workstations. 3D printing, also known as rapid prototyping or additive manufacturing, was once the province of industry to fabricate models from a computer-aided design (CAD) in a layer-by-layer manner. The early adopters in clinical practice have embraced the medical imaging-guided 3D-printed biomodels for their ability to provide tactile feedback and a superior appreciation of visuospatial relationship between anatomical structures. With increasing accessibility, investigators are able to convert standard imaging data into a CAD file using various 3D reconstruction softwares and ultimately fabricate 3D models using 3D printing techniques, such as stereolithography, multijet modeling, selective laser sintering, binder jet technique, and fused deposition modeling. However, many clinicians have questioned whether the cost-to-benefit ratio justifies its ongoing use. The cost and size of 3D printers have rapidly decreased over the past decade in parallel with the expiration of key 3D printing patents. Significant improvements in clinical imaging and user-friendly 3D software have permitted computer-aided 3D modeling of anatomical structures and implants without outsourcing in many cases. These developments offer immense potential for the application of 3D printing at the bedside for a variety of clinical applications. In this review, existing uses of 3D printing in plastic surgery practice spanning the spectrum from templates for facial transplantation surgery through to the formation of bespoke craniofacial implants to optimize post-operative esthetics are described. Furthermore, we discuss the potential of 3D printing to become an essential office-based tool in plastic surgery to assist in preoperative planning, developing intraoperative guidance tools, teaching patients and surgical trainees, and producing patient-specific prosthetics in everyday surgical practice.

Risk factors in idiopathic adhesive capsulitis: a case control study

BACKGROUND The etiology of idiopathic adhesive capsulitis (IAC) of the shoulder is poorly understood. In this case control study, we examine potential risk factors for the development of IAC. METHODS Consecutive patients who presented to the senior author with IAC between 2000 and 2009 were included retrospectively in this case control study. Complete data were available for 87 patients. An age- and sex-matched group of 176 patients who presented to the same practice during the same time period with non-shoulder related orthopedic complaints were recruited as the control group. Health records and patient-completed questionnaires were utilized to identify comorbidities and other risk factors. RESULTS Bivariate analyses demonstrated that diabetes, hypothyroidism, a lower body weight, a lower body mass index (BMI), and a positive family history of IAC were all risk factors for IAC. Diabetes, BMI, and positive family history of IAC remained independent variables with multivariate logistic regression analyses. There was a trend towards increased incidence of Dupuytrens disease in those with IAC, but this was not statistically significant. With regard to racial predilection, being born in the British Isles or having parents/grandparents born in the British Isles were risk factors for IAC. CONCLUSION We confirm diabetes as an independent predictor of IAC. In addition, we identify a possible racial predilection for the development of IAC. Future research is needed to confirm whether a specific genetic component or environmental factors is responsible.

Current Evidence for Postoperative Monitoring of Microvascular Free Flaps: A Systematic Review

BackgroundDespite a plethora of monitoring techniques reported in the literature, only a small number of studies directly address clinical relevant end points, such as the flap salvage rate and false-positive rate. MethodWe conducted a systematic review of current evidence regarding the postoperative monitoring of microvascular free-tissue transfer via extensive electronic and manual search and perusing databases, such as PubMed, Cochrane, American College of Physicians (ACP) Journal Club, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Excerpta Medica Database (EMBASE), and Ovid MEDLINE. The included literature (n = 184 publications) was critically appraised using March 2009 Oxford Centre for Evidence-Based Medicine definitions, focusing on the evidence for the efficacy of each technique in improving the flap salvage rate of compromised flaps. ResultThere is a paucity of outcome-based studies, with only implanted Doppler probes, near-infrared spectroscopy, laser Doppler flowmetry, quantitative fluorimetry, and digital photography assessment using smartphones having been demonstrated in comparative studies to improve flap salvage rate. Currently, the implantable Doppler probe is the technique with the largest number of comparative studies and case series to demonstrate its effectiveness compared with clinical monitoring. ConclusionsFuture studies need to evaluate the most promising monitoring techniques further with a focus on assessing clinically relevant outcomes, such as the flap salvage rate and the false-positive rate, and not simple clinical series reporting patient and physician satisfaction.

Breast Reconstruction Post Mastectomy: Patient Satisfaction and Decision Making.

BackgroundAlthough breast reconstruction has been shown to improve psychological, physical, and sexual well-being, Australia still has one of the lowest reconstruction rates among well-developed countries. This study explores both the quality-of-life benefits of reconstruction and the factors that influence patients’ decisions of whether or not to undergo reconstruction. MethodsThis retrospective cohort study (296 consecutive mastectomy patients from 2000 to 2010) uses an internationally validated questionnaire (BREAST-Q) to evaluate patients’ satisfaction with or without breast reconstruction. In addition, we analyzed factors that influence patients’ decisions of whether to undergo reconstruction. ResultsTwo hundred nineteen patients responded (74%) and of the 143 patients who elected to participate, 79 were in the “reconstruction group” and 64 in the “no-reconstruction group” post mastectomy. Patient demographics and cancer variables of the 2 groups were matched with the exception of age (reconstruction group 9.7 years younger: P < 0.01). The reconstruction group showed statistically significantly higher BREAST-Q scores with regard to satisfaction with the breast (P < 0.0001), psychological well-being (P = 0.0068), and sexual well-being (P = 0.0001). For the reconstruction group, the main reasons for undergoing reconstruction included improved self-image, more clothing choices, and the feeling of overcoming the cancer. One third of non-reconstructed patients still feared that reconstruction would mask cancer recurrence. ConclusionOur study confirms the positive effects of breast reconstruction post mastectomy and identifies reasons that influence patients’ decisions of whether to undergo reconstruction. Breast reconstruction should be seen as an integral part in the comprehensive care of women with breast cancer and an important health care priority in Australia.

3D-printed haptic "reverse" models for preoperative planning in soft tissue reconstruction: a case report.

In reconstructive surgery, preoperative planning is essential for optimal functional and aesthetic outcome. Creating a three‐dimensional (3D) model from two‐dimensional (2D) imaging data by rapid prototyping has been used in industrial design for decades but has only recently been introduced for medical application. 3D printing is one such technique that is fast, convenient, and relatively affordable. In this report, we present a case in which a reproducible method for producing a 3D‐printed “reverse model” representing a skin wound defect was used for flap design and harvesting. This comprised a 82‐year‐old man with an exposed ankle prosthesis after serial soft tissue debridements for wound infection. Soft tissue coverage and dead‐space filling were planned with a composite radial forearm free flap (RFFF). Computed tomographic angiography (CTA) of the donor site (left forearm), recipient site (right ankle), and the left ankle was performed. 2D data from the CTA was 3D‐reconstructed using computer software, with a 3D image of the left ankle used as a “control.” A 3D model was created by superimposing the left and right ankle images, to create a “reverse image” of the defect, and printed using a 3D printer. The RFFF was thus planned and executed effectively, without complication. To our knowledge, this is the first report of a mechanism of calculating a soft tissue wound defect and producing a 3D model that may be useful for surgical planning. 3D printing and particularly “reverse” modeling may be versatile options in reconstructive planning, and have the potential for broad application.

Prosthetic breast reconstruction: indications and update

BACKGROUND Despite 82% of patients reporting psychosocial improvement following breast reconstruction, only 33% patients choose to undergo surgery. Implant reconstruction outnumbers autologous reconstruction in many centres. METHODS A systematic review of the literature was undertaken. Inclusion required: (I) Meta-analyses or review articles; (II) adult patients aged 18 years or over undergoing alloplastic breast reconstruction; (III) studies including outcome measures; (IV) case series with more than 10 patients; (V) English language; and (VI) publication after 1(st) January, 2000. RESULTS After full text review, analysis and data extraction was conducted for a total of 63 articles. Definitive reconstruction with an implant can be immediate or delayed. Older patients have similar or even lower complication rates to younger patients. Complications include capsular contracture, hematoma and infection. Obesity, smoking, large breasts, diabetes and higher grade tumors are associated with increased risk of wound problems and reconstructive failure. Silicone implant patients have higher capsular contracture rates but have higher physical and psychosocial function. There were no associations made between silicone implants and cancer or systemic disease. There were no differences in outcomes or complications between round and shaped implants. Textured implants have a lower risk of capsular contracture than smooth implants. Smooth implants are more likely to be displaced as well as having higher rates of infection. Immediate breast reconstruction (IBR) gives the best aesthetic outcome if radiotherapy is not required but has a higher rate of capsular contracture and implant failure. Delayed-immediate reconstruction patients can achieve similar aesthetic results to IBR whilst preserving the breast skin if radiotherapy is required. Delayed breast reconstruction (DBR) patients have fewer complications than IBR patients. CONCLUSIONS Implant reconstruction is a safe and popular mode of post-mastectomy reconstruction. Evidence exists for the settings in which complications are more likely, and we can now more reliably predict outcomes of reconstruction on an individual basis and assess patient suitability.

Needle fasciotomy for Dupuytren's disease: an Australian perspective

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3D haptic modelling for preoperative planning of hepatic resection: A systematic review

Introduction and background Three dimensional (3D) printing has gained popularity in the medical field because of increased research in the field of haptic 3D modeling. We review the role of 3D printing with specific reference to liver directed applications. Methods A literature search was performed using the scientific databases Medline and PubMed. We performed this in-line with the PRISMA [20] statement. We only included articles in English, available in full text, published about adults, about liver surgery and published between 2005 and 2015. The 3D model of a patients liver venous vasculature and metastasis was prepared from a CT scan using Osirix software (Pixmeo, Gineva, Switzerland) and printed using our 3D printer (MakerBot Replicator Z18, US). To validate the model, measurements from the inferior vena cava (IVC) were compared between the CT scan and the 3D printed model. Results A total of six studies were retrieved on 3D printing directly related to a liver application. While stereolithography (STL) remains the gold standard in medical additive manufacturing, Fused Filament Fabrication (FFF), is cheaper and may be more applicable. We found our liver 3D model made by FFF had a 0.1 ± 0.06 mm margin of error (mean ± standard deviation) compared with the CT scans. Conclusion 3D printing in general surgery is yet to be thoroughly exploited. The most relevant feature of interest with regard to liver surgery is the ability to view the 3D dimensional relationship of the various hepatic and portal veins with respect to tumor deposits when planning hepatic resection. Systematic review registration number: researchregistry1348.

Incidence and overall survival of malignant ameloblastoma.

Background Malignant ameloblastoma, comprising metastasizing ameloblastoma and ameloblastic carcinoma, represents 1.6–2.2% of all odontogenic tumors. Due to its rare nature, malignant ameloblastoma has only been reported in the literature in small case series or case reports. Using the Surveillance, Epidemiology and End-Results (SEER) database, we have performed a population-based study to determine the incidence rate and the absolute survival of malignant ameloblastoma. Method Using the International Classification of Diseases for Oncology (ICD-O) codes 9310/3 and 9270/3, data from the SEER database were used to calculate the incidence rate and absolute survival rate of population with malignant ameloblastoma. Results The overall incidence rate of malignant ameloblastoma was 1.79 per 10 million person/year. The incidence rate was higher in males than females and also higher in black versus white population. The median overall survival was 17.6 years from the time of diagnosis and increasing age was associated with a statistically significant poorer survival. Conclusions To our best knowledge, we report the largest population-based series of malignant ameloblastoma. The incidence rate was 1.79 per 10 million person/year and the overall survival was 17.6 years.

Dupuytren's contracture: an analysis of outcomes of percutaneous needle fasciotomy versus open fasciectomy

Percutaneous needle fasciotomy (PNF) is a minimally invasive technique used to manage Dupuytrens contracture. We compared outcomes of PNF versus open fasciectomy (OF) to examine the suitability of PNF in Australia.