ObjectiveTo develop and validate a method for creating realistic, patient specific replicas of cerebral aneurysms by means of fused deposition modeling.MethodsThe luminal boundaries of 10 cerebral aneurysms, together with adjacent proximal and distal sections of the parent artery, were segmented based on DSA images, and corresponding virtual three-dimensional (3D) surface reconstructions were created. From these, polylactic acid and MakerBot Flexible Filament replicas of each aneurysm were created by means of fused deposition modeling. The accuracy of the replicas was assessed by quantifying statistical significance in the variations of their inner dimensions relative to 3D DSA images. Feasibility for using these replicas as flow phantoms in combination with phase contrast MRI was demonstrated.Results3D printed aneurysm models were created for all 10 subjects. Good agreement was seen between the models and the source anatomy. Aneurysm diameter measurements of the printed models and source images correlated well (r=0.999; p<0.001), with no statistically significant group difference (p=0.4) or observed bias. The SDs of the measurements were 0.5 mm and 0.2 mm for source images and 3D models, respectively. 3D printed models could be imaged with flow via MRI.ConclusionsThe 3D printed aneurysm models presented were accurate and were able to be produced inhouse. These models can be used for previously cited applications, but their anatomical accuracy also enables their use as MRI flow phantoms for comparison with ongoing studies of computational fluid dynamics. Proof of principle imaging experiments confirm MRI flow phantom utility.

Purpose While pancreaticoduodenectomy (PD) has been extensively studied in adults, there are few data pertaining specifically to pediatric patients. We retrospectively analyzed PD-associated morbidity and mortality in pediatric patients. Methods Our analytic cohort included all consecutive patients ≤18 years of age treated at our institution from 1993-2015 who underwent PD. Patient data (demographics, disease characteristics, surgical and adjuvant treatment, length of hospital stay, and postoperative course) were extracted from the medical records. Results We identified 12 children with a median age of 9 years (7 female, 5 male). Final diagnoses were pancreatoblastoma (n=3), solid pseudopapillary tumor (n=3), neuroblastoma (n=2), rhabdomyosarcoma (n=2), and neuroendocrine carcinoma (n=2). Four patients underwent PD for resection of recurrent disease. 75% (9/12 patients) received neoadjuvant therapy. The median operative time was approximately 7 hours with a mean blood loss of 590cc. The distal pancreas was invaginated into the posterior stomach (n=3), into the jejunum (n=5) or directly sewn to the jejunal mucosa (n=4). There were no operative deaths. There were 4 patients (34%) with Grade II complications, 1 with a Grade IIIb complication (chest tube), and 1 with a Grade IV complication (re-exploration). The most common long-term morbidity was pancreas exocrine supplementation (n=10; 83%). Five patients (42%) diagnosed with either solid pseudopapillary tumor or rhabdomyosarcoma are currently alive with a mean survival of 77.4 months. Conclusion Pancreaticoduodenectomy is a feasible management strategy for pediatric pancreatic malignancies and is associated with acceptable morbidity and overall survival. Long-term outcome is most dependent on histology of the tumor. Level of Evidence IV

The sciatic artery - a rare finding on autopsy - and continuation of the inferior gluteal artery has been reported previously. On a routine dissection, bilateral persistent sciatic arteries were found in both thighs of a female cadaver. This provided evidence that the sciatic artery follows the sciatic nerve, supplies the back of the thigh and finally joins the popliteal artery near the knee. The profunda femoris artery was completely absent bilaterally. The present report strengthens the view that the sciatic artery plays a major role in supplying blood to the lower limbs in utero and its existence after birth may have significant clinical importance.