Orthognathic treatment of asymmetry: two cases of "waferless" stereotactic maxillary positioning

We present 2 cases in which navigation-guided surgery was used to correct complex facial asymmetry. The merits and challenges of using stereotactic technology to allow “waferless” positioning of the maxilla in orthognathic surgery are illustrated by patients who were operated on without the use of acrylic wafers to achieve three-dimensional correction of the maxillary deformity. Biometric assessment was made clinically and recorded with computed tomographic (CT) scanning. The operation was planned using Voxim^® software and the operation done with the aid of the Voxim^® navigation system.     

Evaluation of the accuracy of computer-assisted techniques in the interstitial brachytherapy of the deep regions of the head and neck

PurposeWe sought to investigate the feasibility and accuracy of computer-assisted techniques in the interstitial brachytherapy of the deep regions of the head and neck.Materials and MethodsA computer-assisted brachytherapy workflow was applied to 10 patients with tumors in the deep regions of the head and neck. Based on the brachytherapy treatment preplan, we constructed a digital stereotactic model to accurately transfer the virtual plan into the navigation system, and subsequently printed the individual templates. The navigation system and the individual template were combined together to visualize and guide brachytherapy needle implantation. Preoperative and intraoperative image data were reconstructed and registered to measure and analyze the needle deviation.ResultsA total of 58 needles were successfully inserted in 10 patients with the guidance of computer-assisted techniques and a mean deviation of 5.2 mm. The inserting trajectories and depths of the needles were as follows: from the parotid and masseter regions to the infratemporal fossa or skull base, the range was 15.7–74.6 mm; from the submandibular and retromandibular regions to the infratemporal fossa or skull base, the range was 15.6–70.6 mm; from the infraorbital region to the pterygomandibular region, the range was 63.7–69.7 mm; and from the periorbital region to the intraorbital region, the range was 47.6–61.8 mm. The dose distribution met the treatment requirement well.ConclusionsThe computer-assisted interstitial brachytherapy workflow was proven to be feasible and accurate for the deep regions of the head and neck.     

Reconstruction after skin cancer excision through a dermal induction template: our experience

Dermal substitutes offer alternative approaches for wounds of all thicknesses where sufficient donation sites are not available for self‐grafts. Several dermal substitutes are described in literature. This study included 20 patients treated with a dermal induction template after the removal of malignant skin cancers situated in various parts of the body. The participants were especially aged patients with multiple skin cancers, and complex clinical conditions, often affected by pathologies such as cardiopathy, diabetes mellitus, and hypercholesterolaemia, and receiving pharmacological multi‐therapies, particularly antiplatelets and anticoagulants. In many of these patients, the general complex clinical picture provided significant contraindication for complex reconstructive surgery because of the high risk involved. All patients achieved complete healing about 8 weeks after the first surgery. By using a dermal induction template, it was possible to cover substantial loss of substances without the need of autologous tissue, with smoother and less apparent scar, minor occurrence of hypertrophic and retracted scars, better flexibility of healed skin and therefore a better result from an aesthetic point of view.     

A novel computer-assisted surgical technique for revision total knee arthroplasty

Revision total knee arthroplasty (RTKA) is a skill-demanding intervention presenting several technical challenges to the surgeon due to bone deficiencies and lack of anatomical references. Computer-assisted navigation systems can potentially solve these problems. An innovative computer-assisted surgical technique for RTKA is presented. The system is image free. Based on anatomical landmarks acquired on the patient, the system automatically plans the intervention, and provides the surgeon with tools to analyse and modify the proposed plan and to accurately reproduce it on the patient. Although we performed few cases with this navigated procedure, early results obtained demonstrated to be very promising.     

The Glenoid Vault Outer Cortex (GVOC) radiological reference for shoulder arthroplasty evaluated in aging scapulae

BackgroundAccurate glenoid component positioning is an important determinant of outcome in a shoulder arthroplasty surgery. Optimal glenoid placement is determined using bony landmarks of the scapula. The Glenoid Vault Outer Cortex (GVOC) has been recently described as a new, more accurate radiological reference. This has, however, only been evaluated against current standard references in young patients. Further investigation of the GVOC in older patients is therefore warranted. We, therefore, evaluated the effect of aging on the accuracy and stability of the GVOC, in determining glenoid anatomy as compared to the commonly used Scapular Border (SB) plane.MethodsComputed tomography imaging of 129 individual scapulae was obtained retrospectively from a cohort of patients who had undergone either total body or region-specific computed tomography imaging which included the shoulder region. This comprised of 35 males and 33 females (64 and 65 scapulae respectively) who were aged from 30 to 92 years. Imaging of 54 scapulae was from patients aged ≥60 years. The accuracy of the GVOC plane was then assessed against the SB plane.ResultsIn all patients, the mean difference between estimates using the GVOC plane and the GR (actual) was 2.2° (standard deviation [SD], 4.2) for version, and 1.8° (SD, 4.9) for inclination (P < .001). This contrasted with values of 7.6° (SD, 7.6) for version, and 22.9° (SD, 10.8) for inclination when using the SB reference plane (P < .001). Within the group aged ≥60 years, the mean difference between estimates using the GVOC plane and the glenoid rim (actual) was 3.2° (SD, 4.7) for version and 1.9° (SD, 3.1) for inclination, (P < .001). This contrasted to 10.0° (SD, 7.2) for version, and 23.4° (SD, 10.7) for inclination when using the SB plane (P < .001).Separately it was noted that the GVOC’s relationship to the glenoid rim remained constant throughout aging as opposed to the SB which changed significantly over time effecting estimates of glenoid retroversion.ConclusionsThe GVOC is a new plane of reference developed specifically for the use in shoulder arthroplasty. It is shown to be more accurate and stable in the aging scapulae than the currently used SB plane. The future development of guides and planning softwares that utilize the GVOC may provide an important opportunity for improved accuracy and outcome in shoulder arthroplasty.     

术中导航校准技术辅助下青少年特发性脊柱侧凸顶椎区置钉精确性研究

【摘要】 目的：比较青少年特发性脊柱侧凸（adolescent idiopathic scoliosis,AIS）顶椎区相同椎弓根类型在导航及导航校准技术辅助下置钉的精确性及偏出方向,并分析影响导航置钉偏移的相关因素及导航校准技术的临床意义。方法：回顾性分析自2017年10月～2020年10月,在我院明确诊断为AIS并在导航辅助下行经后路脊柱侧凸矫形内固定术治疗的41例患者,依据术中是否使用导航校准技术,将41例患者分为两组：导航组（n=22）和校准组（n=19）。收集两组患者基本信息,记录两组患者Risser征,术前、术后Cobb角,术后1年时矫形率,根据付长峰椎弓根分型系统对两组患者顶椎区椎弓根分型（A、B、C、D、E型）,依据Rao分型评估两组相同椎弓根类型的置钉精确性。结果：校准组A、B、C型椎弓根优良置钉率（96.4%、87.8%、84.0%）显著高于导航组（79.2%、70.5%、56.7%）,且凹凸双侧0级钉率显著高于导航组,同时校准组B型椎弓根及其凹凸双侧3级钉率（4.1%、2.0%、6.3%）及C型椎弓根凸侧2级钉置钉率（11.1%）显著低于导航组（12.4%、11.1%、13.7%、50.0%）,两组间差异均具有统计学意义（P＜0.05）。此外,校准组A、B、C型椎弓根外侧皮质破壁率（33.3%、33.3%、60.0%）显著低于导航组（64.0%、38.6%、73.1%）,同时校准组A型椎弓根椎体前壁穿破率（0.0%）及C型椎弓根凹侧外侧皮质破壁率（66.7%）显著低于导航组（24.0%、77.8%）,而B型椎弓根内侧皮质穿破率（41.7%）高于导航组（40.9%）,但其凹侧内侧皮质穿破率（36.4%）显著低于导航组（33.3%）,两组间差异均具有统计学意义（P＜0.05）。两组间均未发生脊髓、神经血管损伤等严重并发症。结论：与传统导航相比,导航校准技术在术中能够有效地预防导航偏移,显著提高AIS顶椎区A、B、C型椎弓根置钉精确性,降低误置螺钉外侧壁穿孔率及B型椎弓根凹侧内侧壁穿孔率,提高手术的安全性。     

肝胆外科从数字虚拟人、三维可视化到数字智能化发展的现状

数字智能化肝胆外科的发展经历了十几年的演进过程,从数字虚拟人技术到质控化、同质化三维可视化精准诊疗体系的建立;从三维可视化到数字智能化技术临床转化及诊疗模式的转换;实现了疾病的经验性诊断到深度学习智能化诊断与治疗和经验性手术到多模态影像实时手术导航的技术创新;从肿瘤的形态学诊断深入到分子影像学精准诊断的研究。在这个过程中只有不断地进行研究创新、理论创新和技术创新才能给数字智能化外科赋予新的生命力。未来,从关键分子功能可视化实现肝癌分子、细胞层面边界界定和早诊早治,对改变肝癌患者肝切除术后的预后具有重大的临床价值。此外,为了实现智能化肝切除手术导航,突破技术瓶颈,研发具有自动导航技术、机器学习智能规划技术和多模态影像融合技术的智能化机器人实时导航肝切除手术系统具有重要的临床意义,给数字智能化肝胆外科的发展带来了新的机遇和挑战。     

Can rotatory knee laxity be predicted in isolated anterior cruciate ligament surgery?

Purpose

Despite the overall success of the surgical anterior cruciate ligament (ACL) reconstruction, some patients still present with instability symptoms even after the surgery, mainly due to the presence of associated lesions. At present, the pivot shift test has been reported to be the benchmark to assess rotatory knee laxity. The purpose of this study was to quantitatively evaluate rotatory knee laxity at time-zero in order to determine whether detected post-reconstruction laxity was predictable by its value measured before the reconstruction, which was hypothized to be influenced by the presence of associated lesions.

Methods

Rotatory knee laxity was retrospectively analysed in 42 patients, including two different ACL reconstructions. The maximal anterior displacement and the absolute value of the posterior acceleration reached during the reduction of the tibial lateral compartment were intra-operatively acquired by using a navigation system and identified as discriminating parameters. For each parameter, statistical linear regression analysis (line slope and intercept) was performed between pre- and post-reconstruction values.

Results

No statistically significant influence of the initial posterior acceleration on the post-reconstruction outcome was found (line slope, p > 0.05), although a statistically significant line intercept was indeed identified (p < 0.001). A statistically significant influence on the surgery outcome was instead found for the initial value of the anterior tibial displacement (line slope = 0.39, p = 0.004), meaning that, on average, about 40 % of the post-reconstruction lateral compartment displacement could be explained by the corresponding pre-reconstruction value. Both of these findings highlighted the importance of intra-operative quantification of rotatory knee laxity to identify correct indications for the surgery.

Conclusions

This study provided important implications for the future possibility of defining a quantifying tool able to assess rotatory knee laxity during ACL reconstruction. This could allow detection of additional injuries to secondary restraints by easily performing rotatory knee laxity tests, which in turn could reduce post-surgical recurrence of knee instability.     

Synthesis of Co–Fe 1D Nanocone Array Electrodes Using Aluminum Oxide Template

Porous anodic alumina oxide (AAO) obtained via two-step anodization is a material commonly used as a template for fabricating 1D nanostructures. In this work, copper and cobalt-iron 1D nanocones were obtained by an electrodeposition method using AAO templates. The templates were produced using two-step anodization in H₂C₂O₄. The Co–Fe nanostructures are characterized by homogeneous pore distribution. The electrocatalytic activity of the produced nanomaterials was determined in 1 M NaOH using the linear sweep voltammetry (LSV) and chronopotentiometry (CP) methods. These materials can be used as catalysts in the water-splitting reaction. The sample’s active surface area was calculated and compared with bulk materials.     

基于中国人脑图谱Chinese2020配准的阿尔茨海默病患者静息态fMRI

目的 探讨基于中国人脑图谱Chinese2020配准的静息态功能MR数据分析在阿尔茨海默病（AD）患者中的应用价值。方法 收集12例AD患者（AD组）和17名健康志愿者（正常对照组）,基于中国人脑图谱Chinese2020和传统标准脑图谱ICBM152配准对静息态数据进行全脑分析,运用低频振幅（ALFF）和局部一致性（ReHo）分析方法,评估AD患者脑局部神经元自发活动的变化,并比较基于2种脑图谱配准计算的AD患者ALFF和ReHo差异性脑区的分布。结果 基于2种脑图谱的数据分析均发现,与正常对照组比较,AD组右侧颞上回、右侧楔前叶和右侧角回ALFF值减低,左侧小脑、左侧颞极、颞上回和颞中回ALFF升高（P均<0.05）;AD组左侧颞中回、右侧颞下回、左侧三角部额下回和左侧楔叶ReHo值减低,左侧小脑ReHo值升高（P均<0.05）。基于Chinese2020分析获得的相同的差异脑区平均灰质占比[ALFF：（38.85±17.88）%;ReHo：（54.69±13.28）%]高于基于传统脑图谱ICBM152分析[ALFF：（33.75±14.70）%;ReHo：（45.66±12.35）%],但差异无统计学意义（P=0.68、0.21）。结论 基于中国人脑图谱Chinese2020配准的静息态功能磁共振数据分析在检测中国AD患者的局部神经元自发活动方面较传统的西方人脑图谱更准确。