David H. Ballard

Clinical Applications of 3D Printing: Primer for Radiologists

Three-dimensional (3D) printing refers to a number of manufacturing technologies that create physical models from digital information. Radiology is poised to advance the application of 3D printing in health care because our specialty has an established history of acquiring and managing the digital information needed to create such models. The 3D Printing Task Force of the Radiology Research Alliance presents a review of the clinical applications of this burgeoning technology, with a focus on the opportunities for radiology. Topics include uses for treatment planning, medical education, and procedural simulation, as well as patient education. Challenges for creating custom implantable devices including financial and regulatory processes for clinical application are reviewed. Precedent procedures that may translate to this new technology are discussed. The task force identifies research opportunities needed to document the value of 3D printing as it relates to patient care.

Three-dimensional printing of bioactive hernia meshes: In vitro proof of principle

THREE-DIMENSIONAL (3-D) printing of operative instruments, prostheses, and implants is a topic of considerable interest in both scientific literature and popular media. Surgical meshes are widely used in hernia repair and may be a candidate for specialized 3-D printing. On-demand, intraoperative 3-D printing of surgical meshes has the potential to facilitate patient-specific medicine. Synthetic and biologic meshes come in many different commercial forms. In hernia repair, these prefabricated meshes often require modification to match patient-specific anatomy. 3-D printing of meshes tailored to intraoperative measurements, patient anatomy, specific situations, and patient comorbidities could improve technical facility, decrease waste, and may even save costs. 3-D-printedmeshes can be fabricated in real time using biocompatible, permanent, or absorbable material alone or in combination. Mesh size, shape, material, distribution of grommets/rivets, thickness, and flexibility can be customized with 3-D printing and allow reinforced areas to be created as suture points. Mesh pore size or weave can also be modified. In addition, 3-D-printed meshes can be used as a depot for localizeddrugdelivery, achieving therapeutic local levels while avoiding systemic toxicity. Previous work has demonstrated the

Logistics of Three-dimensional Printing: Primer for Radiologists

The Association of University Radiologists Radiology Research Alliance Task Force on three-dimensional (3D) printing presents a review of the logistic considerations for establishing a clinical service using this new technology, specifically focused on implications for radiology. Specific topics include printer selection for 3D printing, software selection, creating a 3D model for printing, providing a 3D printing service, research directions, and opportunities for radiologists to be involved in 3D printing. A thorough understanding of the technology and its capabilities is necessary as the field of 3D printing continues to grow. Radiologists are in the unique position to guide this emerging technology and its use in the clinical arena.

Three-Dimensional Printing of Cell Exclusion Spacers (CES) for Use in Motility Assays

PurposeCell migration/invasion assays are widely used in commercial drug discovery screening. 3D printing enables the creation of diverse geometric restrictive barrier designs for use in cell motility studies, permitting on-demand assays. Here, the utility of 3D printed cell exclusion spacers (CES) was validated as a cell motility assay.MethodsA novel CES fit was fabricated using 3D printing and customized to the size and contour of 12 cell culture plates including 6 well plates of basal human brain vascular endothelial (D3) cell migration cells compared with 6 well plates with D3 cells challenged with 1uM cytochalasin D (Cyto-D), an F-actin anti-motility drug. Control and Cyto-D treated cells were monitored over 3xa0days under optical microscopy.ResultsDay 3 cell migration distance for untreated D3 cells was 1515.943μmu2009±u200910.346μm compared to 356.909μmu2009±u200938.562μm for the Cyt-D treated D3 cells (pu2009<u20090.0001). By day 3, untreated D3 cells reached confluency and completely filled the original voided spacer regions, while the Cyt-D treated D3 cells remained significantly less motile.ConclusionsCell migration distances were significantly reduced by Cyto-D, supporting the use of 3D printing for cell exclusion assays. 3D printed CES have great potential for studying cell motility, migration/invasion, and complex multi-cell interactions.

3D Printed Antibiotic and Chemotherapeutic Eluting Catheters for Potential Use in Interventional Radiology: In Vitro Proof of Concept Study

RATIONALE AND OBJECTIVESnAdditive manufacturing may be used as a form of personalized medicine in interventional radiology by allowing for the creation of customized bioactive constructs such as catheters that can act as a form of localized drug delivery. The purpose of the present in vitro study was to use three-dimensional (3D) printing to construct bioactive-laden bioabsorbable catheters impregnated with antibiotics and chemotherapeutics.nnnMATERIALS AND METHODSnPolylactic acid bioplastic pellets were coated with the powdered bioactive compounds gentamicin sulfate (GS) or methotrexate (MTX) to incorporate these drugs into the 3D printed constructs. The pellets were then extruded into drug-impregnated filament for fused deposition modeling 3D printing. Computer-aided design files were generated in the shapes of 14-F catheters. Scanning electron microscope imaging was used to visualize the presence of the additive powders on the surface of the printed constructs. Elution profiles were run on the antibiotic-laden catheter and MTX-laden catheters. Antibiotic-laden catheters were tested on bacterial broth and plate cultures.nnnRESULTSnBoth GS and MTX catheter constructs had sustained drug release up to the 5-day limit of testing. The 3D printed GS-enhanced catheters inhibited all bacterial growth in broth cultures and had an average zone of inhibition of 858u2009±u2009118u2009mm2 on bacterial plates, whereas control catheters had no effect.nnnCONCLUSIONnThe 3D printing manufacturing method to create instruments in percutaneous procedures is feasible. Further in vivo studies will substantiate these findings.

Multimodality Imaging Review of Anorectal and Perirectal Diseases with Clinical, Histologic, Endoscopic, and Operative Correlation, Part II: Infectious, Inflammatory, Congenital, and Vascular Conditions

A broad spectrum of pathology affects the rectum, anus, and perineum, and multiple imaging modalities are complementary to physical examination for assessment and treatment planning. In this pictorial essay, correlative imaging, endoscopic, pathologic, and operative images are presented for a range of rectal, perirectal, and perineal disease processes, including infectious/inflammatory, traumatic, congenital/developmental, vascular, and miscellaneous conditions. Key anatomic and surgical concepts are discussed, including radiological information pertinent for surgical planning, and current operative approaches of these anatomic spaces to assist radiologists in comprehensive reporting for gastroenterologists and surgeons.

Multimodality Imaging Review of Anorectal and Perirectal Diseases With Histological, Endoscopic, and Operative Correlation, Part I: Anatomy and Neoplasms

A broad spectrum of pathology affects the rectum, anus, and perineum and understanding of its relevant anatomy is important in accurate reporting, particularly in rectal cancer. In this pictorial essay, correlative imaging, endoscopic, pathologic, and operative images are presented to illustrate normal anorectal anatomy and neoplastic conditions that affect the anus and rectum. A particular case-based focus is given to rectal adenocarcinoma with pelvic MR and surgical histopathology. Additionally, carcinoid tumor, gastrointestinal stromal tumor, condylomata acuminata, squamous cell carcinoma, melanoma, and metastatic disease about the rectum and anus are reviewed.

Fibroepithelial polyp causing urethral obstruction: Diagnosis by cystourethrogram

Fibroepithelial polyps of the urethra are rare benign tumors that predominantly affect males in childhood or adolescence. In this report, we present a case of a 3-year-old boy in acute urinary retention with a urethral fibroepithelial polyp manifesting as a large filling defect on voiding cystourethrogram and successfully managed endoscopically with transurethral resection.

Necrotizing infection of the heart

A case of necrotizing infection of the heart is presented. A 70-year-old woman presented with vague chest and abdominal pain. CT of the abdomen and pelvis was initially obtained, which demonstrated gas in the myocardium of the left ventricle. Subsequent chest CT, endoscopy, and abdominal surgical exploration did not reveal perforated viscus or diaphragm compromise. At median sternotomy, the inferior wall of the heart was found to be necrotic. Culture of the excised tissue grew E. coli. The patient expired shortly after surgical exploration.

Addressing Burnout in Radiologists

Burnout is a global health problem affecting physicians across all medical specialties. Radiologists, in particular, experience high rates of burn out, and this trend has only continued to worsen. The Promoting Health and Wellness for Radiologists Task Force of the Association of University Radiologists-Radiology Research Alliance presents a review of the prevalence, causes, and impact of burnout among radiology faculty and trainees, and a discussion on strategies for overcoming burnout and promoting overall health and well-being among radiologists.