Learning condyle repositioning during orthognathic surgery with a surgical navigation system

Condyle repositioning during bilateral sagittal splint osteotomy (BSSO) is a challenging step for the inexperienced surgeon. We aimed to demonstrate the benefit of navigation for learning the condyle repositioning. We treated 100 patients who underwent a BSSO. A trainee performed the condyle repositioning of one side in two phases. In the first one, the trainee positioned without watching the screen of the Orthopilot Navigation system (ONS). In the second one, the trainee could use the ONS to replace the condyle. Heuristic, anatomical and functional scores of each phase were recorded. Heuristic (17% vs. 75%; p < 0.0001), anatomical (35% vs. 86%; p < 0.0001) and functional (14% vs. 56%; p < 0.0001) scores were significantly greater with the ONS. The ONS is a promising and original intraoperative learning tool for the repositioning of the condyle during BSSO.     

Registration methods for surgical navigation of the mandible: a systematic review

Image-to-patient registration in navigated mandibular surgery is complex due to the mobile nature of the mandible compared with other craniofacial bones. As a result, surgical navigation is rarely employed in the mandibular region. This systematic review provides an overview of the different registration methods that are used for surgical navigation of the mandible. A systematic search was performed in the MEDLINE Ovid, Scopus, and Embase databases on March 25, 2021. Search terms included synonyms for mandibular surgery, surgical navigation, and registration methods. Articles about navigated mandibular surgery, where the registration method was explicitly mentioned, were included. The database search yielded a total of 2952 articles, from which 81 articles remained for analysis. Four main registration methods were identified: point registration, surface registration, hybrid registration, and computer vision-based registration. The mobility of the mandible is accounted for by either keeping the mandible in a fixed position during preoperative imaging and surgery, or by tracking the mandibular movements. Although different registration methods are available for navigated mandibular surgery, there is always a trade-off between accuracy, registration time, usability, and invasiveness. Future studies should focus on testing the different methods in larger patient studies and should report the registration accuracy.     

“One-piece” patient-specific reconstruction plate for double-barrel fibula-based mandibular reconstruction

Segmental mandibular defects require reconstruction. The fibula flap serves as a versatile flap in restoring mandibular contour and bony height. With the advances in computer-aided design and additive manufacturing technology, an innovative “one-piece” patient-specific reconstruction plate to facilitate double-barrel fibula flap shaping and bone securing was developed; the plate is described in this study. The “one-piece” plate is fabricated with individualized specifications and is mainly composed of three components: the long-bar reconstruction plate, a short-bar plate, and connecting bars. Our initial experiences showed that mandibular reconstructive surgery was greatly facilitated by the “one-piece” reconstruction plate for double-barrel fibula flap reconstruction and achieved satisfactory outcomes. A well-designed clinical trial is required to confirm the superiority of the “one-piece” reconstruction plate in the future. ClinicalTrials.gov registration: NCT03057223.     

基于CT三维重建技术绘制骨折地图的临床应用进展

CT三维重建技术已经广泛应用于骨折诊断及其分型。基于CT三维重建的骨折地图绘制技术,通过绘制骨折模型来直观展现骨折线的形态学,包括骨折线的起止、走行、骨折面积等。骨折地图绘制技术为骨折诊断、骨折分型、治疗方案选择、手术内固定物设计、骨折好发部位统计、骨折标准化模型制定均提供了一个全新的方法。本文将回顾目前国内外包括对于肩胛骨骨折、胫骨远端骨折、尺骨冠状突骨折、胫骨平台骨折、桡骨小头骨折、股骨转子间外侧壁骨折、髋臼四边体骨折等骨折地图的研究进展,归纳总结了以上各个骨折模型的骨折好发部位及骨折地图绘制技术在骨折分型等方面的应用,并探讨骨折地图的临床应用前景及骨折地图绘制技术存在的问题等。     

New method for quantification of the relative severity and (a)symmetry of isolated metopic synostosis

Trigonocephaly is the result of premature fusion of the metopic suture and its severity can vary widely. However, there is no gold standard for quantification of the severity. This study was performed to quantify severity using the Utrecht Cranial Shape Quantifier (UCSQ) and to assess forehead symmetry. Nineteen preoperative non-syndromic trigonocephaly patients (age ≤1 year) were included for the analysis of severity and symmetry. Severity according to the UCSQ was based on the following combined variables: forehead width and relative skull elongation. The UCSQ was compared to the most established quantification methods. A high correlation was found between the UCSQ and visual score (r = 0.71). Moderate to negligible correlation was found between the UCSQ and frontal angle, binocular distance, inter-ocular distance, and frontal stenosis. Additionally, correlation between the visual score and these established quantification methods was negligible. Assessment of the frontal peak (a)symmetry (ratio of right to left triangle area in the curve) showed a mean right versus left triangle area ratio of 1.4 (range 0.9–2.4). The results suggest that the UCSQ is appropriate for the quantification of severity based on the high correlation with clinical judgement. Furthermore, a larger triangle area right than left was unexpectedly found, indicating forehead asymmetry.     

儿童颌面部骨折诊疗研究进展

儿童处于生长发育特殊阶段，其颌面部解剖结构、牙列情况及心理状态与成年人有明显区别。颌面部骨折患儿常出现面部发育畸形、张口受限、咬合关系紊乱等，严重影响患儿的日常生活。因此，儿童颌面部骨折的诊疗一直是临床上的难题，也是国内外的研究热点。颌面部骨折好发于青少年，损伤原因多为意外跌倒、交通伤及运动伤。近年来，数字化外科技术为儿童颌面部骨折提供精确的诊断及微创的治疗。国内外学者对于儿童颌面部骨折治疗理念逐渐倾向于手术治疗，选择可吸收材料对儿童颌面部骨折进行固定，降低对儿童面部发育的影响。长期随访对于儿童颌面部骨折患儿具有重要意义，有助于监测患儿面部发育情况。此外，临床医生应注意患儿的心理状态。对于创伤较重或发现有心理问题的患儿，应尽早干预治疗。文章就近年儿童颌面部骨折流行病学特点、诊断、治疗原则及伴发的心理问题做一综述。     

局部晚期非小细胞肺癌三维适形放射治疗致放射性肺损伤相关因素探讨

目的 探讨局部晚期非小细胞肺癌患者接受三维适形放射治疗引起放射性肺损伤(radiation-induced lung injury,RILI)的影响因素.方法 选取2014-2015年三维适形放射治疗局部晚期非小细胞肺癌患者64例,采用美国肿瘤放射治疗协作组(radiotherapy oncology group,RTOG)标准评估RILI级别,以放疗结束后3月内发生≥2级RILI作为终点事件,用SPSS 19.0统计软件进行统计学分析,χ2检验进行单因素分析,logistics多元回归模型进行多因素分析.结果 64例中23例发生放射性肺损伤,发生率35.94%;单因素分析发现性别、年龄、病理类型KPS评分、化疗周期数、肿瘤分期及肿瘤直径与RILI发生率无关(P>0.05);而吸烟、慢性阻塞性肺疾病、是否接受同期化疗、放疗总剂量、接受超过某剂量照射的肺体积占全肺总体积的百分比(肺V5、V10、V20、V30)、平均肺受量(mean lung dose,MLD)及计划靶体积(planning target volume,PTV)与RILI发生率有关(P<0.05).多因素分析显示是否接受同期化疗、肺V5、计划靶体积及放疗总剂量是RILI发生率的独立因素.结论 行三维适形放射治疗局部晚期非小细胞肺癌老年患者,若同期化疗、肺V5及放疗总剂量高、计划靶体积大,则需高度重视防治RILI.     

Reconstruction of the temporal contour for traumatic tissue loss using a CAD/CAM-prefabricated titanium implant-case report

INTRODUCTION: A 16-year-old Arab boy had suffered from a severe head injury including an intracranial haematoma. Despite replantation of the bone flap later on, the cosmetic result was very unfavourable due to partial resorption of the reinserted bone and atrophy of the right temporalis muscle. AIM: For contour reconstruction of both soft and hard tissues the boy was transferred from Saudi Arabia. METHOD: A spiral CT was obtained and the contour was reconstructed using a new algorithm for surface generation. RESULT: The resulting titanium implant was inserted without complications or the need for revision. The cosmetic result was good and corresponded to the preoperative digital planning. CONCLUSION: Techniques of computer-assisted implant prefabrication and surgery may include special algorithms for considering soft tissues including contour deficits of the temporalis muscle.