Three-dimensional Printing for Renal Cancer and Surgical Planning

The Role of Three-dimensional Model in Preoperative Communication Before Partial Nephrectomy and Postoperative Management

Objective

To investigate the role of the three-dimensional (3D) image reconstruction technique in preoperative communication before partial nephrectomy (PN) and postoperative follow-up.

Methods

A retrospective study was performed with 158 renal cancer patients treated with PN at our center from May 1, 2017 to April 30, 2019. 81 patients (group A) had preoperative communication using the 3D reconstruction technique, while 77 patients (group B) did not. The surgeon explained the anatomical structure, tumor characteristics, and surgical approach in detail to the two groups of patients. Each patient completed a questionnaire. The loss to follow-up rate over a 3-year period was counted for both groups, and non-cancer-related serious complications such as renal failure and cardio-cerebrovascular disease were observed. This research did not include patients who returned for follow-up care owing to associated complications such as postoperative chronic kidney disease. Comparisons between two groups were performed using the Mann-Whitney U test and chi-square test.

Results

All patients showed no statistically significant differences in basic clinical parameters, such as age, gender, body mass index, tumor size, and R.E.N.A.L. score (P ​> ​0.05). In group A, patients were significantly more likely to experience understanding of renal anatomy (P ​= ​0.001), characteristics of renal cell carcinoma (P ​= ​0.003), surgical approach (P ​= ​0.007), and relief of preoperative anxiety (P ​= ​0.013). The follow-up adherence at 3 years postoperatively in group A and group B was 21 cases and 10 cases, respectively (P ​= ​0.041). In addition, glomerular filtration rate < 60 ​mL/min/1.73 ​m² or serum creatinine > 186 ​μmol/L at 3 years after surgery occurred in 5 patients in group A and 13 in group B (P ​= ​0.034), and a systolic blood pressure rise greater than 20 ​mmHg occurred in 9 patients in group A and 18 in group B (P ​= ​0.041).

Conclusions

The use of 3D reconstruction techniques for preoperative communication can successfully improve patients' perception and comprehension of kidney tumors and PN, as well as help to prevent serious postoperative non-cancer-related complications.

Hybrid Additive Fabrication of a Transparent Liver with Biosimilar Haptic Response for Preoperative Planning

Due to the complexity of liver surgery, the interest in 3D printing is constantly increasing among hepatobiliary surgeons. The aim of this study was to produce a patient-specific transparent life-sized liver model with tissue-like haptic properties by combining additive manufacturing and 3D moulding. A multistep pipeline was adopted to obtain accurate 3D printable models. Semiautomatic segmentation and registration of routine medical imaging using 3D Slicer software allowed to obtain digital objects representing the structures of interest (liver parenchyma, vasculo-biliary branching, and intrahepatic lesion). The virtual models were used as the source data for a hybrid fabrication process based on additive manufacturing using soft resins and casting of tissue-mimicking silicone-based blend into 3D moulds. The model of the haptic liver reproduced with high fidelity the vasculo-biliary branching and the relationship with the intrahepatic lesion embedded into the transparent parenchyma. It offered high-quality haptic perception and a remarkable degree of surgical and anatomical information. Our 3D transparent model with haptic properties can help surgeons understand the spatial changes of intrahepatic structures during surgical manoeuvres, optimising preoperative surgical planning.

Role of 3D printing in surgical education for robotic urology procedures

During the past 5 years, the body of literature surrounding the utilization of three-dimensional (3D) printing in the field of urology has grown exponentially. Incentivized by work hour restrictions, patient safety initiatives, and inspired by technical advances in biomaterials and rapid printing strategies, this emerging, and fascinating area of research has begun to make headway into clinical practice. However, concerns about cost, limited understanding of the technical processes involved, and lack of its potential uses remain barriers to its widespread adoption. We examined existing published literature on how 3D printing technologies have been utilized in the field of Urology to enhance pre-operative planning, revitalize surgical training, and modernize patient education, with particular focus on, robotic surgery. To date, 3D-printed models have been used and studied most commonly in the preoperative planning for nephron-sparing surgeries during the treatment of renal masses, where the challenges of complex renal anatomy and benefits of reducing renal ischemic injury create the most intuitive value. Prostate models are the second most common, particularly in the planning of nerve-sparing procedures. Early studies have demonstrated sufficient realism and educational effectiveness. Subsequent studies demonstrated improved surgeon confidence, operative performance, and optimized patient outcomes including high levels of patient satisfaction. Realistic, accurate, and reasonably priced models can currently be generated within hours using standard desktop 3D printers. While primarily utilized as anatomic replicas of diseased organs that restore a sense of haptic feedback lost in robotic procedures, innovations in polymers, improvements in 3D printer host and modeling software, and upgrades in printer hardware allow this technology to serve as a comprehensive, interactive, simulation platform that can be a critical surgical decision making as well as an effective teaching tool. As Urologists continue to rapidly diversify and iterate upon this adaptive modality, the benefits in patient outcomes will likely outpace the diminishing drawbacks, and we may well see the next revolution in surgical education, robotic techniques, and personalized medicine concurrently.

Medical Three-Dimensional Printing in Zoological Medicine

Medical 3-dimensional printing allows the creation of anatomic models by using a sequence of computer software programs. Diagnostic imaging data are used to create a physical model that allows clinicians to plan for surgical procedures and create prosthetics and surgical implants and instruments, among other applications. Its use in zoological medicine is limited, but is an area with a great growth potential. This publication reviews the process of creating a 3-dimensional anatomic model, its application in human and small animal medicine and surgery, and reviews peer-reviewed data regarding its use in exotic animals, wildlife, and zoo animals.

3D printed modeling contributes to reconstruction of complex chest wall instability

Background

Three-dimensional printed models are increasingly used in many fields including medicine and surgery, but their use in the planning and execution of complex chest wall reconstruction has not been adequately described. In cases of non-union or prior attempts at chest wall reconstruction which have failed, there can be substantial deviations from expected chest wall anatomy. We report a novel technique for pre-operative planning and surgical execution of complex chest wall reconstruction, assisted by 3D printing. Our objective was to utilize 3-D volumetric modeling coupled with 3-D printing to produce patient-specific models for chest wall reconstruction in complex cases.

Methods

Soft tissue reconstruction 0.75 mm slice thickness computed tomography (CT) imaging data was loaded into medical CAD software for segmentation. Lung, muscle, foreign bodies, and bony structureswere separated due to the differences in density between them. The 3D volumetric mesh was then quality checked and stereolithography files (STL) were made which were able to be utilized by the 3D printer. The STL files were exported to a Objet 500 material jetting printer that utilized several UV light cured photopolymers.

Results

As an example case, we discuss a 55 year old male who underwent resuscitative thoracotomy. In the early post-operative period, he developed a pulmonary hernia in the 6th intercostal space, repaired with wire cerclage reapproximation of ribs. He developed a symptomatic mobile chest wall at the site of prior repair with additional concern for dissociated anterior cartilage. In preparation for operative repair, a 3D printed model was created, demonstrating fractured cartilage anteriorly as well a saw effect through the six and seventh ribs. An additional model was created using the normal ribs from the right side in mirror image reflection to quantify the degree and precise geometry of mal-alignment to the left chest. These models were then utilized to determine the operative approach via a thoracotomy incision to remove the cerclage wires, followed by parasternal incision, reduction and plating of the sternocostal non-union bursa Rib non-unions were plate stabilized. Repeat imaging in follow-up has demonstrated continued appropriate alignment and the patient reported improvement in his symptoms.

Conclusion

At present, the cost of 3-D printing remains substantial, but given the improved planning in complex cases, this cost may be recaptured in the reduction of operative time and improved outcomes with reduced re-operation rates. We believe that the early adoption of this technology by surgeons can help improve surgical quality and provide enhanced individualized patient care. These patient-specific models facilitate identification of features which are often not detected with standard 3-D reconstructed CT rendering. Centers should pursue the integration of 3-D printed models into their practice and active collaborations between surgeons and modeling experts should be sought at every available opportunity.

Radiological Society of North America (RSNA) 3D printing Special Interest Group (SIG): guidelines for medical 3D printing and appropriateness for clinical scenarios

Medical three-dimensional (3D) printing has expanded dramatically over the past three decades with growth in both facility adoption and the variety of medical applications. Consideration for each step required to create accurate 3D printed models from medical imaging data impacts patient care and management. In this paper, a writing group representing the Radiological Society of North America Special Interest Group on 3D Printing (SIG) provides recommendations that have been vetted and voted on by the SIG active membership. This body of work includes appropriate clinical use of anatomic models 3D printed for diagnostic use in the care of patients with specific medical conditions. The recommendations provide guidance for approaches and tools in medical 3D printing, from image acquisition, segmentation of the desired anatomy intended for 3D printing, creation of a 3D-printable model, and post-processing of 3D printed anatomic models for patient care.

Principles of three-dimensional printing and clinical applications within the abdomen and pelvis

Improvements in technology and reduction in costs have led to widespread interest in three-dimensional (3D) printing. 3D-printed anatomical models contribute to personalized medicine, surgical planning, and education across medical specialties, and these models are rapidly changing the landscape of clinical practice. A physical object that can be held in one's hands allows for significant advantages over standard two-dimensional (2D) or even 3D computer-based virtual models. Radiologists have the potential to play a significant role as consultants and educators across all specialties by providing 3D-printed models that enhance clinical care. This article reviews the basics of 3D printing, including how models are created from imaging data, clinical applications of 3D printing within the abdomen and pelvis, implications for education and training, limitations, and future directions.

[Imaging in individualized uro-oncology]

The recent introduction of new diagnostic techniques has revolutionized uro-oncolgy. In addition to multiparametric magnetic resonance imaging (mpMRI), prostate-specific membrane antigen positron-emission tomography (PSMA-PET) plays an increasingly import role in daily practice. The introduction of three-dimensional (3D) printing technologies in the context of robot-assisted uro-oncological surgery represents a first step towards individualized 3D imaging. In the era of immunotherapy, imaging is challenged by new diagnostic criteria (iRECIST) and immune-related adverse effects.