【Abstract】ObjectiveTo evaluate the value of MR imaging with a contrast-enhanced multi-phasic isotropic volumetric interpolated breath-hold examination (VIBE) in diagnosis of primary liver carcinoma. MethodsThirty-two consecutive patients with surgical-pathologically confirmed 42 foci of primary carcinoma of liver underwent comprehensive MR examination of the upper abdomen, routine two-dimensional (2D) T1WI and T2WI images were acquired before administration of Gd-DTPA for contrast enhancement. Then, contrast-enhanced multi-phasic VIBE was acquired followed by 2D T1WI images. The lesion appearances on hepatic arterial, portal venous and equilibrium phases of VIBE sequence were carefully observed along with delineation of hepatic arterial and portal venous structures. The lesion detection rates and lesion characterization ability were compared among various MR sequences. Results33(78.6%), 30(71.4%), 38(90.5%) and 42(100%) foci were displayed respectively on T2WI, non-enhanced T1WI, enhanced T1WI and enhanced 3D-VIBE images (P＜0.05). The hepatic arterial anatomy of 30 patients （93.8%） and the portal venous structure of 31 patients （96.9%） were clearly depicted on enhanced 3D-VIBE images. Using MIP and MPR reconstruction techniques, the feeding arteries of 14 foci and draining vein of 12 foci were clearly displayed.ConclusionHigh-quality 3D-VIBE images are not only better than 2D images in lesion detection and characterization for primary liver carcinoma, but also able to provide much more information about hepatic vascular anatomy.
ObjectiveTo summarize the current research progress of three-dimensional (3D) printing technique for spinal implants manufacture. MethodsThe recent original literature concerning technology, materials, process, clinical applications, and development direction of 3D printing technique in spinal implants was reviewed and analyzed. ResultsAt present, 3D printing technologies used to manufacture spinal implants include selective laser sintering, selective laser melting, and electron beam melting. Titanium and its alloys are mainly used. 3D printing spinal implants manufactured by the above materials and technology have been successfully used in clinical. But the problems regarding safety, related complications, cost-benefit analysis, efficacy compared with traditional spinal implants, and the lack of relevant policies and regulations remain to be solved. Conclusion3D printing technique is able to provide individual and customized spinal implants for patients, which is helpful for the clinicians to perform operations much more accurately and safely. With the rapid development of 3D printing technology and new materials, more and more 3D printing spinal implants will be developed and used clinically.
ObjectiveTo explore the feasibility of the repair and reconstruction of large talar lesions with three-dimensional (3D) printed talar components by biomechanical test.MethodsSix cadaveric ankle specimens were used in this study and taken CT scan and reconstruction. Then, 3D printed talar component and osteotomy guide plate were designed and made. After the specimen was fixed on an Instron mechanical testing machine, a vertical pressure of 1 500 N was applied to the ankle when it was in different positions (neutral, 10° of dorsiflexion, and 14° of plantar flexion). The pressure-bearing area and pressure were measured and calculated. Then osteotomy on specimen was performed and 3D printed talar components were implanted. And the biomechanical test was performed again to compare the changes in pressure-bearing area and pressure.ResultsBefore the talar component implantation, the pressure-bearing area of the talus varied with the ankle position in the following order: 10° of dorsiflexion > neutral position > 14° of plantar flexion, showing significant differences between positions ( P<0.05). The pressure exerted on the talus varied in the following order: 10° of dorsiflexion < neutral position < 14° of plantar flexion, showing significant differences between positions (P<0.05). The pressure-bearing area and pressure were not significantly different between before and after talar component implantations in the same position (P>0.05). The pressure on the 3D printed talar component was not significantly different from the overall pressure on the talus (P>0.05).ConclusionApplication of the 3D printed talar component can achieve precise repair and reconstruction of the large talar lesion. The pressure on the repaired site don’t change after operation, indicating the clinical feasibility of this approach.
Three-dimensional (3D) visualization technology can well characterize lung nodules, accurately locate lung nodules, accurately identify lung anatomical structures, shorten operation time, reduce intraoperative and postoperative complications, and make thoracoscopic precise lung resection safer and more efficient. However, the mastery of 3D reconstruction technology in some hospitals still needs to be improved. Due to the time and economic cost of 3D printing, the development of this technology is restricted. With the application and improvement of 3D visualization technology in more centers in the future, the development of precise lung resection will be more extensive. This article reviewed the progress on 3D visualization technology in thoracoscopic precise lung resection.
Objective To compare changes in retinal and choroidal blood flow in the macular area of eyes with idiopathic macular hole (IMH), fellow eyes, and normal eyes. Additionally, the correlation between these blood flow changes and the occurrence and development of IMH. Methods A cross-sectional study. From January 2023 to January 2024, 47 patients (47 eyes) diagnosed with IMH (IMH group) in Department of Ophthalmology of The Second Hospital of Hebei Medical University were included in the study. The contralateral eye of IMH eyes was assigned to the contralateral eye group. Healthy volunteers with matched gender and age were selected as the normal control group. Swept-source optical coherence tomography angiography was used to acquire the vessel density (VD) of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) in the areas within 0-1 mm and 1-6 mm around the fovea, including the superior, temporal, inferior, and nasal regions. Additionally, the choroidal blood flow area (CBFA) and three-dimensional choroidal vascular index (3D-CVI) were measured. The minimum linear diameter (MLD) and base diameter (BD) of the IMH were manually measured. Spearman correlation analysis was performed to evaluate the correlation between the size of the IMH and the various vascular parameters. ResultsCompared with the normal control group, the SCP-VD in the 3rd stage (t=1.298, P=0.009) and 4th stage (t=1.264, P＜0.000) eyes in the IMH group was significantly decreased, with statistical significance; the DCP-VD (t=1.958, 2.150, 1.712, 1.667; P=0.027, ＜0.000, ＜0.000, ＜0.000) and 3D-CVI (t=0.027, 0.030, 0.024, 0.023; P=0.005, 0.003, ＜0.000, ＜0.000) in eyes of all stages were significantly decreased, with statistical significance; the CBFA in eyes of stages 2-4 was significantly decreased, with statistical significance (t=0.027, 0.022, 0.021; P=0.028, 0.002, 0.002). Compared with the contralateral eye group, the DCP-VD and 3D-CVI in the IMH group were significantly reduced, with statistical significance (Z=?3.289, ?2.704; P=0.001, 0.007). Pairwise comparisons between eyes of different stages in the IMH group showed that SCP-VD was significantly different between stage 2 and stage 4 (t=1.776, P=0.008); DCP-VD was significantly different between stage 1 and stage 3, and stage 1 and stage 4 (t=1.685, 1.661; P=0.002, 0.000). Correlation analysis showed that SCP-VD was negatively correlated with MLD and BD (r=?0.508, ?0.408; P=0.002, 0.014); DCP-VD was negatively correlated with BD (r=?0.410, P=0.013). Compared with the normal control group, the nasal CBFA in stage 3 and 4 IMH eyes (t=0.149, 0.145; P=0.005, 0.002), and the nasal 3D-CVI in stage 1 and 3 IMH eyes (t=0.030, 0.027; P=0.002, ＜0.000) were significantly decreased, with statistical significance. ConclusionsThe SCP-VD, DCP-VD, CBFA, and 3D-CVI in IMH eyes were significantly reduced. SCP-VD showed a negative correlation with MLD and BD, while DCP-VD was only negatively correlated with BD.
The interventional therapy of vascular stent implantation is a popular treatment method for cardiovascular stenosis and blockage. However, traditional stent manufacturing methods such as laser cutting are complex and cannot easily manufacture complex structures such as bifurcated stents, while three-dimensional (3D) printing technology provides a new method for manufacturing stents with complex structure and personalized designs. In this paper, a cardiovascular stent was designed, and printed using selective laser melting technology and 316L stainless steel powder of 0?10 μm size. Electrolytic polishing was performed to improve the surface quality of the printed vascular stent, and the expansion behavior of the polished stent was assessed by balloon inflation. The results showed that the newly designed cardiovascular stent could be manufactured by 3D printing technology. Electrolytic polishing removed the attached powder and reduced the surface roughness Ra from 1.36 μm to 0.82 μm. The axial shortening rate of the polished bracket was 4.23% when the outside diameter was expanded from 2.42 mm to 3.63 mm under the pressure of the balloon, and the radial rebound rate was 2.48% after unloading. The radial force of polished stent was 8.32 N. The 3D printed vascular stent can remove the surface powder through electrolytic polishing to improve the surface quality, and show good dilatation performance and radial support performance, which provides a reference for the practical application of 3D printed vascular stent.
ObjectiveTo determine the feasibility of fabricating molds using a three-dimensional (3D) printer for producing customized bone cement for repairing bone defect. MethodsBetween February 2015 and March 2016, 13 patients with bone defects were treated. There were 9 males and 4 females with an average age of 38.4 years (range, 20-58 years), including 7 cases of chronic osteomyelitis, 3 cases of bone tuberculosis, 2 cases of bone tumor, and 1 case of ischemic necrosis. The defect located at the humerus in 3 cases, at the femur in 4 cases, and at the tibia in 6 cases. The defect ranged from 4.5 to 8.9 cm in length (mean, 6.7 cm). Before operation, Mimics10.01 software was used to design cement prosthesis, 3-matic software to design shaping module which was printed by 3D technology. After removal of the lesion bone during operation, bone cement was filled into the shaping module to prepare bone cement prosthesis for repairing defect. ResultsThe measurement result from Image J software showed that the match index of interface between the mirror restored digital and bone interface was 95.1%-97.4% (mean, 96.3%); the match index of interface between bone cement prosthesis and bone interface was 91.2%-94.7% (mean, 93.2%). It was one time success during separation between formed bone cement and shaping module without any shatter or fall off. All incisions healed by first intention. The cases were followed up 5-17 months (mean, 9.4 months). X-ray films and CT scans showed good position of bone cement prosthesis without any fracture; no peripheral fracture occurred. Conclusion3D printing customized bone cement shaping module can shorten the operation time, and customized bone cement prothesis has good match with bone interface, so it can avoid further adjustment and accord with the biomechanical rules of surgical site.
Objective To evaluate the effectiveness of combining three-dimensional printing (3DP) models with three-dimensional visualization (3DV) technology in the teaching of thoracoscopic sublobar resection. Methods From March 2024 to June 2025, 150 interns were randomly assigned by envelope method to the 3DV, 3DP, and combined (3DV+3DP) groups. Three theoretical tests and score changes were used to assess short- and long-term teaching outcomes, and a questionnaire survey was conducted to analyze learning experience. Results After teaching, scores improved significantly in all groups (P<0.001), with the greatest increase in the combined group (47.18±5.81), which was higher than the 3DV and 3DP groups (P<0.001 and P=0.002, respectively). At 1 month, scores declined in all groups (P=0.028), but the combined group showed the smallest decrease (?6.94 ± 6.05). The combined group also showed the most pronounced advantage in spatial cognition (38.0%). Conclusion Innovative 3DP+3DV instructional model improves sublobar lung resection teaching and shows better long-term retention and spatial cognition.
With the development of three-dimensional (3D) printing technology, more and more researches have focused on its application in the region of intervertebral fusion materials; the prospects are worth looking forward to. This article reviews the researches about 3D printing technology in spinal implants, and summarizes the materials and printing technology applied in the field of spinal interbody fusion, and the shortcomings in the current research and application. With the rapid development of 3D printing technology and new materials, more and more 3D printing spinal interbodies will be developed and used clinically.
Objective To investigate the cl inical directive significance of three-dimensional reconstruction of CT in treating mandibular angle hypertrophy. Methods Between March 2009 and January 2011, 18 patients with mandibular angle hypertrophy were treated using the three-dimensional reconstruction technology of CT. All patients were female, aged20-36 years with an average of 25 years. Eighteen patients included: 14 single mandibular angle hypertrophy, 3 mandibular angle hypertrophy with masseter hypertrophy, and 1 mandibular angle hypertrophy with bilateral asymmetry; 6 cases of ptosis of mandibular angle, 9 cases of prominent mandibular angle, and 3 cases of introversive mandibular angle. According to the types of mandibular angle hypertrophy, the surgical methods could be correctly chosen. The procedure was planned and simulated; the osteotomy l ine was marked and the osteotomy was measured on the workstations of three-dimensional reconstruction. Results No fracture of mandible occurred in the operation. Facial nerve temporary attack occurred in 1 case and recovered at 3 months after operation. All patients were followed up 6-12 months (mean, 7.6 months). After 6 months of operation, the effectiveness was satisfactory in 15 cases, basically satisfactory in 2 cases, and unsatisfactory in 1 case (bilateral asymmetry). Conclusion Based on three-dimensional reconstruction technology of CT, surgical design performed on the model will promote the accuracy of operation. Basically symmetrical appearances can be achieved with satisfactory results.