Changes in Microwave Ablation Zone Dimensions after Transarterial Embolization in an Ex Vivo Human Kidney Perfusion Model.

PURPOSE: To utilize a novel ex vivo perfused human renal model and quantify microwave ablation (MWA) size differences in renal tissue when combining MWA with transarterial embolization (TAE). MATERIALS AND METHODS: Human kidneys (n = 5) declined for transplantation were obtained and connected to a fluoroscopy-compatible ex vivo perfusion system. Two ablations-1 standard MWA and 1 TAE-MWA-were performed in each kidney for 2 minutes at 100 W using a MWA system (Solero Angiodynamics). MWA alone was performed in the upper pole. In the lower pole, MWA was performed after TAE with 40-90 µm radiopaque microspheres to achieve angiographic stasis. Ablation zones of coagulative necrosis were sectioned along the long axis and segmented for maximal short-axis diameter (SAD) and long-axis diameter (LAD) measurements. RESULTS: A total of 10 ablations (5 MWAs and 5 TAE-MWAs) were performed in 5 human kidneys. TAE-MWA resulted in significantly increased SAD, LAD, volume, and sphericity compared with standard MWA ± SD, with mean measurements as follows (5 standard MWAs ± SD vs 5 TAE-MWAs ± SD, 2-tailed t-test): (a) SAD, 1.8 cm (SD ± 0.1) versus 2.5 cm (SD ± 0.1) (P < .001); (b) LAD, 2.9 cm (SD ± 0.3) versus 3.2 cm (SD ± 0.1) (P = .039); (c) volume, 5.0 mL (SD ± 0.5) versus 11.0 mL (SD ± 0.7) (P < .001); and (d) sphericity, 0.4 (SD ± 0.2) versus 0.6 (SD ± 0.1) (P = .049). Histology demonstrated no differences in TAE-MWA other than concentrated microspheres. CONCLUSIONS: This ex vivo human kidney perfusion model confirmed that combined MWA-TAE significantly increased ablation size and spherical shape compared with MWA alone.

Mechanical, bioactive, and long-lasting antibacterial properties of a Ti scaffold with gradient pores releasing iodine ions.

The ideal bone implant would effectively prevent aseptic as well as septic loosening by minimizing stress shielding, maximizing bone ingrowth, and preventing implant-associated infections. Here, a novel gradient-pore-size titanium scaffold was designed and manufactured to address these requirements. The scaffold features a larger pore size (900 µm) on the top surface, gradually decreasing to small sizes (600 µm to 300 µm) towards the center, creating a gradient structure. To enhance its functionality, the additively manufactured scaffolds were biofunctionalized using simple chemical and heat treatments so as to incorporate calcium and iodine ions throughout the surface. This unique combination of varying pore sizes with a biofunctional surface provides highly desirable mechanical properties, bioactivity, and notably, long-lasting antibacterial activity. The target mechanical aspects, including low elastic modulus, high compression, compression-shear, and fatigue strength, were effectively achieved. Furthermore, the biofunctional surface exhibits remarkable in vitro bioactivity and potent antibacterial activity, even under conditions specifically altered to be favorable for bacterial growth. More importantly, the integration of small pores alongside larger ones ensures a sustained high release of iodine, resulting in antimicrobial activity that persisted for over three months, with full eradication of the bacteria. Taken together, this gradient structure exhibits obvious superiority in combining most of the desired properties, making it an ideal candidate for orthopedic and dental implant applications.

Strontium-loaded 3D intramedullary nail titanium implant for critical-sized femoral defect in rabbits.

The treatment of critical-sized bone defects has long been a major problem for surgeons. In this study, an intramedullary nail shaped three-dimensional (3D)-printed porous titanium implant that is capable of releasing strontium ions was developed through a simple and cost-effective surface modification technique. The feasibility of this implant as a stand-alone solution was evaluated using a rabbit's segmental diaphyseal as a defect model. The strontium-loaded implant exhibited a favorable environment for cell adhesion, and mechanical properties that were commensurate with those of a rabbit's cortical bone. Radiographic, biomechanical, and histological analyses revealed a significantly higher amount of bone ingrowth and superior bone-bonding strength in the strontium-loaded implant when compared to an untreated porous titanium implant. Furthermore, one-year histological observations revealed that the strontium-loaded implant preserved the native-like diaphyseal bone structure without failure. These findings suggest that strontium-releasing 3D-printed titanium implants have the clinical potential to induce the early and efficient repair of critical-sized, load-bearing bone defects.

Impact of prior abdominal surgery on the outcomes after robotic - assisted laparoscopic radical prostatectomy: single center experience

ABSTRACT Purpose: To evaluate the influence of prior abdominal surgery on the outcomes after robotic-assisted laparoscopic radical prostatectomy (RALP). Materials and Methods: We retrospectively analyzed patients with prostate cancer who underwent RALP between June 2012 and February 2015 at our institution. Patients with prior abdominal surgery were compared with those without prior surgery while considering the mean total operating, console, and port-insertion times; mean estimated blood loss; positive surgical margin rate; mean duration of catheterization; and rate of complications. Results: A total of 203 patients who underwent RALP during the study period were included in this study. In all, 65 patients (32%) had a prior history of abdominal surgery, whereas 138 patients (68%) had no prior history. The total operating, console, and port-insertion times were 328 and 308 (P=0.06), 252 and 242 (P=0.28), and 22 and 17 minutes (P=0.01), respectively, for patients with prior and no prior surgery. The estimated blood losses, positive surgical margin rates, mean durations of catheterization, and complication rates were 197 and 170 mL (P=0.29), 26.2% and 20.2% (P=0.32), 7.1 and 6.8 days (P=0.74), and 12.3% and 8.7% (P=0.42), respectively. Furthermore, whether prior abdominal surgery was performed above or below the umbilicus or whether single or multiple surgeries were performed did not further affect the perioperative outcomes. Conclusions: Our results suggest that RALP can be performed safely in patients with prior abdominal surgery, without increasing the risk of complications.