IntraBrain Injector (IBI): A StereotacticGuided Device for Repeated Delivery of Therapeutic Agents Into the Brain Parenchyma

Background@#To deliver therapeutics into the brain, it is imperative to overcome the issue of the blood-brain-barrier (BBB). One of the ways to circumvent the BBB is to administer therapeutics directly into the brain parenchyma. To enhance the treatment efficacy for chronic neurodegenerative disorders, repeated administration to the target location is required. However, this increases the number of operations that must be performed. In this study, we developed the IntraBrain Injector (IBI), a new implantable device to repeatedly deliver therapeutics into the brain parenchyma. @*Methods@#We designed and fabricated IBI with medical grade materials, and evaluated the efficacy and safety of IBI in 9 beagles. The trajectory of IBI to the hippocampus was simulated prior to surgery and the device was implanted using 3D-printed adaptor and surgical guides. Ferumoxytol-labeled mesenchymal stem cells (MSCs) were injected into the hippocampus via IBI, and magnetic resonance images were taken before and after the administration to analyze the accuracy of repeated injection. @*Results@#We compared the planned vs. insertion trajectory of IBI to the hippocampus.With a similarity of 0.990 ± 0.001 (mean ± standard deviation), precise targeting of IBI was confirmed by comparing planned vs. insertion trajectories of IBI. Multiple administrations of ferumoxytol-labeled MSCs into the hippocampus using IBI were both feasible and successful (success rate of 76.7%). Safety of initial IBI implantation, repeated administration of therapeutics, and long-term implantation have all been evaluated in this study. @*Conclusion@#Precise and repeated delivery of therapeutics into the brain parenchyma can be done without performing additional surgeries via IBI implantation.

Breast-Conserving Surgery after Neoadjuvant Chemotherapy Using a Three-Dimensional-Printed Surgical Guide Based on Supine Magnetic Resonance Imaging: A Case Report / 한국유방암학회지

Tumor localization in patients receiving neoadjuvant chemotherapy (NACT) is challenging because substantial therapeutic remission of the original tumor after NACT is often noted.Currently, there is no guidance device that allows for an accurate estimation of the resection range in breast-conserving surgery after NACT. To increase the accuracy of tumor resection, we used a 3-dimensional-printed breast surgical guide based on magnetic resonance imaging (MRI) in the supine position for a breast cancer patient who underwent breast-conserving surgery after NACT. Using this device, the breast tumor with apparent therapeutic changes after NACT on imaging was successfully removed with clear resection margins by identifying the original tumor site in the affected breast. Irrespective of whether the residual tumor area after NACT is well defined, it is possible to confirm and target the tumor area on pre-NACT MRI using this device.

Breast-Conserving Surgery after Neoadjuvant Chemotherapy Using a Three-Dimensional-Printed Surgical Guide Based on Supine Magnetic Resonance Imaging: A Case Report / 한국유방암학회지

Tumor localization in patients receiving neoadjuvant chemotherapy (NACT) is challenging because substantial therapeutic remission of the original tumor after NACT is often noted.Currently, there is no guidance device that allows for an accurate estimation of the resection range in breast-conserving surgery after NACT. To increase the accuracy of tumor resection, we used a 3-dimensional-printed breast surgical guide based on magnetic resonance imaging (MRI) in the supine position for a breast cancer patient who underwent breast-conserving surgery after NACT. Using this device, the breast tumor with apparent therapeutic changes after NACT on imaging was successfully removed with clear resection margins by identifying the original tumor site in the affected breast. Irrespective of whether the residual tumor area after NACT is well defined, it is possible to confirm and target the tumor area on pre-NACT MRI using this device.

A Review of Three-Dimensional Printing Technology for Medical Applications

Three-dimensional (3D) printing technology, with additive manufacturing, can aid in the production of various kinds of patient-specific medical devices and implants in medical fields, which cannot be covered by mass production systems for producing conventional devices/implants. The simulator-based medical image demonstrates the anatomical structure of the disease, which can be used for education, diagnosis, preparation of treatment plan and preoperative surgical guide, etc. The surgical guide is used as a patient-specific medical device for guiding incision, resection, insertion, and marking. As 3D printers can output materials that can be inserted into the human body, the patient-specific implant device that reflects the patient's anatomy and surgical plan could be of relevance. In addition, patient-specific aids, including gibs, splints, prostheses, and epitheses, could be used for a better outcome. Finally, bio-printing is also used to cultivate cells to produce functional artificial tissues.

Three-Dimensional Printing: Basic Principles and Applications in Medicine and Radiology

The advent of three-dimensional printing (3DP) technology has enabled the creation of a tangible and complex 3D object that goes beyond a simple 3D-shaded visualization on a flat monitor. Since the early 2000s, 3DP machines have been used only in hard tissue applications. Recently developed multi-materials for 3DP have been used extensively for a variety of medical applications, such as personalized surgical planning and guidance, customized implants, biomedical research, and preclinical education. In this review article, we discuss the 3D reconstruction process, touching on medical imaging, and various 3DP systems applicable to medicine. In addition, the 3DP medical applications using multi-materials are introduced, as well as our recent results.

The Prevalence of Lumbar Spine Facet Joint Osteoarthritis and Its Association with Low Back Pain in Selected Korean Populations

BACKGROUND: This study was to evaluate the association of lumbar spine facet joint osteoarthritis (LSFJOA) identified by multi-detector computed tomography (MDCT) with age and low back pain (LBP) in an adult community-based population in Korea. METHODS: A sample of 472 participants (age range, 20 to 84 years) who underwent MDCT imaging for abdominal or urological lesions, not for chief complaints of LBP, were included in this study. LSFJOA based on MDCT findings was characterized using four grades of osteoarthritis of the facet joints. The prevalence of LSFJOA according to age group (below 40 years, 40-49 years, 50-59 years, 60-69 years, and above 70 years), gender, and spinal level was analyzed using chi-square tests and the association between LBP and LSFJOA adjusting for age, gender, and spine level was analyzed using multiple binary logistic regression test. RESULTS: Eighty-three study subjects (17.58%) had LSFJOA (grade > or = 2). The prevalence of LSFJOA was not associated with gender (p = 0.092). The prevalence of LSFJOA increased with age (p = 0.015). The highest prevalence of LSFJOA was observed at L4-5 in men (p = 0.001) and at L5-S1 in women (p = 0.003), and at L5-S1 in the overall population (p = 0.000). LSFJOA was not associated with LBP in men (p = 0.093) but was associated with LBP in women (p = 0.003), especially at L3-4 (p = 0.018) and L5-S1 (p = 0.026). CONCLUSIONS: The prevalence of LSFJOA based on the computed tomography imaging was 17.58% in the adult community Korean population. The prevalence of LSFJOA increased with age, and the highest prevalence was noted at L5-S1. LSFJOA was not associated with LBP at any spinal level and age except at L3-4 and L5-S1 in women.

Relationship Between Uncommon Computed Tomography Findings and Clinical Aspects in Patients With Acute Pyelonephritis

PURPOSE: Computed tomography (CT) has become popular in the diagnosis of acute pyelonephritis (APN) and its related complications in adults. The aim of this study was to investigate the relationship between uncommon CT findings and clinical and laboratory data in patients with APN. MATERIALS AND METHODS: From July 2009 to July 2012, CT findings and clinical data were collected from 125 female patients with APN. The six uncommon CT findings (excluding a wedge-shaped area of hypoperfusion in the renal parenchyma) studied were perirenal fat infiltration, ureteral wall edema, renal abscess formation, pelvic ascites, periportal edema, and renal scarring. The clinical parameters analyzed were the age and body mass index of the patients as well as the degree and duration of fever. Laboratory parameters related to inflammation and infection included white blood cell count, C-reactive protein (CRP) level, erythrocyte sedimentation rate, pyuria, and bacteriuria. RESULTS: The most common CT finding was perirenal fat infiltration (69 cases, 55%). A longer duration of fever, higher CRP level, and grade of pyuria were related with perirenal fat infiltration (p=0.010, p=0.003, and p=0.049, respectively). The CRP level was significantly higher in patients with renal abscess and ureteral wall edema (p=0.005 and p=0.015, respectively). CONCLUSIONS: The uncommon CT findings that were related to aggravated clinical and laboratory parameters of APN patients were perirenal fat infiltration, ureteral wall edema, and renal abscess formation. The inflammatory reaction and tissue destruction may be more aggressive in patients with these CT findings.

Clinical Application of 3-D Conformal Radiotherapy for Carcinoma of the Ethmoid Sinus: I. Comparative Analysis Between Conventional 2-D and 3-D Conformal Plans / 대한치료방사선과학회지

PURPOSE: This is study of whether 3-D conformal radiotherapy for carcinomas of the ethmoid sinus were better than those treated with conventional 2-D plan. MATERIALS AND METHODS: The 3-D conformal treatment plans were compared with conventional 2-D plans in 4 patients with malignancy of the ethmoid sinus. Isodose distribution, dose statistics, and dose volume histogram of the planning target volume were used to evaluate differences between 2-D and 3-D plans. In addition, the risk of radiation exposure of surrounding normal critical organs are evaluated by means of point dose calculation and dose volume histogram. RESULTS : 3-D conformal treatment plans for each patient that the better tumor coverages by the planning target volume with improved dose homogeneity, compared to 2-D conventional treatment plans in the same patient. On the other hand, the radiation dose distributions to the surrounding normal tissue organs, such as the orbit and optic nerves are not significantly reduced with our technique, but a substantial sparing in the brain stem and optic chiasm for each patient. CONCLUSION : Our findings represented the potential advantage of 3-D treatment planning for dose homogeniety as well as sparing of the normal tissue surrounding the tumor. However, further investigational studies are required to define the clinical benefit.