3D printed temporal bones for preoperative simulation and planning.

OBJECTIVE: Demonstrate the utility of 3D printed temporal bone models in individual patient preoperative planning and simulation. METHODS: 3D models of the temporal bone were made from 5 pediatric and adult patients at a tertiary academic hospital with challenging surgical anatomy planned for cochlear implantation or exteriorization of cholesteatoma with complex labyrinthine fistula. The 3D models were created from CT scan used for preoperative planning, simulation and intraoperative reference. The utility of models was assessed for ease of segmentation and production and impact on surgery in regard to reducing intraoperative time and costs, improving safety and efficacy. RESULTS: Three patients received cochlear implants, two exteriorization of advanced cholesteatoma with fistulas (1 internal auditory canal/cochlea, 1 all three semicircular canals). Surgical planning and intraoperative referencing to the simulations by the attending surgeon and trainees significantly altered original surgical plans. In a case of X-linked hereditary deafness, optimal angles and rotation maneuvers for cochlear implant insertion reduced operating time by 93 min compared to the previous contralateral side surgery. Two cochlear implant cases planned for subtotal petrosectomy approach due to aberrant anatomy were successfully approached through routine mastoidectomy. The cholesteatoma cases were successfully exteriorized without necessitating partial labyrinthectomy or labyrinthine injury. There were no complications. CONCLUSION: 3D printed models for simulation training, surgical planning and use intraoperatively in temporal bone surgery demonstrated significant benefits in designing approaches, development of patient-specific techniques, avoidance of potential or actual complications encountered in previous or current surgery, and reduced surgical time and costs.

Clinical situations for which 3D printing is considered an appropriate representation or extension of data contained in a medical imaging examination: adult cardiac conditions.

BACKGROUND: Medical 3D printing as a component of care for adults with cardiovascular diseases has expanded dramatically. A writing group composed of the Radiological Society of North America (RSNA) Special Interest Group on 3D Printing (SIG) provides appropriateness criteria for adult cardiac 3D printing indications. METHODS: A structured literature search was conducted to identify all relevant articles using 3D printing technology associated with a number of adult cardiac indications, physiologic, and pathologic processes. Each study was vetted by the authors and graded according to published guidelines. RESULTS: Evidence-based appropriateness guidelines are provided for the following areas in adult cardiac care; cardiac fundamentals, perioperative and intraoperative care, coronary disease and ischemic heart disease, complications of myocardial infarction, valve disease, cardiac arrhythmias, cardiac neoplasm, cardiac transplant and mechanical circulatory support, heart failure, preventative cardiology, cardiac and pericardial disease and cardiac trauma. CONCLUSIONS: Adoption of common clinical standards regarding appropriate use, information and material management, and quality control are needed to ensure the greatest possible clinical benefit from 3D printing. This consensus guideline document, created by the members of the RSNA 3D printing Special Interest Group, will provide a reference for clinical standards of 3D printing for adult cardiac indications.