Differences in Demographic and Radiographic Characteristics between Patients with Visible and Invisible T1 Slopes on Lateral Cervical Radiographic Images

Introduction: The T1 slope is important for cervical surgical planning, and it may be invisible on radiographic images. The prevalence of T1 invisible cases and the differences in demographic and radiographic characteristics between patients whose T1 slopes are visible or invisible remains unexplored. Methods: This pilot study aimed to evaluate the differences in these characteristics between outpatients whose T1 slopes were visible or invisible on radiographic images. Patients (n = 60) who underwent cervical radiography, whose T1 slope was confirmed clearly, were divided into the visible (V) group and invisible (I) group. The following radiographic parameters were measured: (1) C2-7 sagittal vertical axis (SVA), (2) C2-7 angle in neutral, flexion, and extension positions. Results: Based on the T1 slope visibility, 46.7% of patients were included in group I. The I group had significantly larger C2-7 SVA than the V group for males (p < 0.05). The C2-7 SVA tended to be larger in the I group, without significant difference for females (p = 0.362). Discussion: The mean C2-7 angle in neutral and flexion positions was not significantly different between the V and I groups for either sex. The mean C2-7 angle in the extension position was greater in the V group. The T1 slope was invisible in males with high C2-7 SVA.

Accuracy of Mixed Reality Combined With Surgical Navigation Assisted Oral and Maxillofacial Tumor Resection

ObjectiveTo evaluate the feasibility and accuracy of mixed reality combined with surgical navigation in oral and maxillofacial tumor surgery.MethodsRetrospective analysis of data of seven patients with oral and maxillofacial tumors who underwent surgery between January 2019 and January 2021 using a combination of mixed reality and surgical navigation. Virtual surgical planning and navigation plan were based on preoperative CT datasets. Through IGT-Link port, mixed reality workstation was synchronized with surgical navigation, and surgical planning data were transferred to the mixed reality workstation. Osteotomy lines were marked with the aid of both surgical navigation and mixed reality images visualized through HoloLens. Frozen section examination was used to ensure negative surgical margins. Postoperative CT datasets were obtained 1 week after the surgery, and chromatographic analysis of virtual osteotomies and actual osteotomies was carried out. Patients received standard oncological postoperative follow-up.ResultsOf the seven patients, four had maxillary tumors and three had mandibular tumors. There were total of 13 osteotomy planes. Mean deviation between the planned osteotomy plane and the actual osteotomy plane was 1.68 ± 0.92 mm; the maximum deviation was 3.46 mm. Chromatographic analysis showed error of ≤3 mm for 80.16% of the points. Mean deviations of maxillary and mandibular osteotomy lines were approximate (1.60 ± 0.93 mm vs. 1.86 ± 0.93 mm). While five patients had benign tumors, two had malignant tumors. Mean deviations of osteotomy lines was comparable between patients with benign and malignant tumors (1.48 ± 0.74 mm vs. 2.18 ± 0.77 mm). Intraoperative frozen pathology confirmed negative resection margins in all cases. No tumor recurrence or complications occurred during mean follow-up of 15.7 months (range, 6-26 months).ConclusionThe combination of mixed reality technology and surgical navigation appears to be feasible, safe, and effective for tumor resection in the oral and maxillofacial region.

Protocol for Multi-Stage Treatment of Temporomandibular Joint Ankylosis in Children and Adolescents

Treatment of temporomandibular ankylosis is challenging and frequently leads to re-ankylosis, relapse, dangerous complications and, in turn, the need for multiple operations. In this article, we present a protocol for the treatment of ankylosis of the temporomandibular joints that assumes earlier intervention with the assistance of 3D virtual surgical planning (3DVSP) and custom biomaterials for better and safer surgical outcomes. Thirty-three patients were treated due to either uni- or bilateral temporomandibular ankylosis. Twenty individuals received temporomandibular prosthesis, whereas seventeen required simultaneous 3D virtual surgical/planned orthognathic surgery as the final correction of the malocclusion. All patients exhibited statistically significant improvements in mouth opening (from 1.21 ± 0.74 cm to 3.77 ± 0.46 cm) and increased physiological functioning of the mandible. Gap arthroplasty and aggressive rehabilitation prior to temporomandibular prosthesis (TMJP) placement were preferred over costochondral autografts. The use of 3DVSP and custom biomaterials enables more precise, efficient and safe procedures to be performed in the paediatric and adolescent population requiring treatment for temporomandibular ankylosis.

Surgical Margins After Computer-Assisted Mandibular Reconstruction: A Retrospective Study

Purpose: The use of virtual surgical planning in head and neck surgery is growing strongly. In the literature, its validity, accuracy and clinical utility for mandibular reconstruction are widely documented. Virtual planning of surgical bone resection and reconstruction takes place several days before surgery and its very sensitive nature can negatively affect an intervention aimed at maximum precision in term of oncological safety.Methods: The study focuses on a retrospective evaluation of the surgical margins in 26 consecutive cases with oral cavity malignancy and who underwent computer-assisted mandibular resection/reconstruction guided by the different types of bone, periosteal and peri-mandibular tissue involvement. The goal was to analyze the strategic and technical aspects useful to minimize the risk of positive or close margins and to vary the reconstructive strategy in the case of intraoperative findings of a non-radical planned resection.Results: No intraoperative or perioperative complications occurred. In 20 patients, virtual surgical planning permitted mandibular reconstruction to be performed using composite fibular free flaps, characterized by high accuracy and negative bone margins. In the remaining 6 patients, also virtually planned but otherwise reconstructed due to poor general condition (advanced age, severe comorbidity), negative bone margins were obtained. Intraoperative enlargement of the resection was carried out in one case and positive soft tissue margins were observed in another case.Conclusion: The results were satisfactory in terms of oncological radicality and precision. The functional benefits and reduction in operating times, previously demonstrated in other articles also by the authors, seem to justify the side effects related to the risk of modifying the planned surgery. During virtual planning, the surgeons must bear in mind that an unexpected progression of the tumor or a limited planned resection will entail modifying the extent of the resection intraoperatively and nullifying the virtual planning on which the reconstruction was based. Further investigations are necessary to clarify all aspects of virtual surgical planning in this setting.

Utility of Three-Dimensional Printing for Preoperative Assessment of Children with Extra-Cranial Solid Tumors: A Systematic Review

Background: In cases with solid tumors, preoperative radiological investigations provide valuable information on the anatomy of the tumor and the adjoining structures, thus helping in operative planning. However, due to a two-dimensional view in these investigations, a detailed spatial relationship is difficult to decipher. In contrast, three-dimensional (3D) printing technology provides a precise topographic view to perform safe surgical resections of these tumors. This systematic review aimed to summarize and analyze current evidence on the utility of 3D printing in pediatric extra-cranial solid tumors. Methods: The present study was registered on PROSPERO—international prospective register of systematic reviews (registration number: CRD42020206022). PubMed, Embase, SCOPUS, and Google Scholar databases were explored with appropriate search criteria to select the relevant studies. Data were extracted to study the bibliographic information of each article, the number of patients in each study, age of the patient(s), type of tumor, organ of involvement, application of 3D printing (surgical planning, training, and/or parental education). The details of 3D printing, such as type of imaging used, software details, printing technique, printing material, and cost were also synthesized. Results: Eight studies were finally included in the systematic review. Three-dimensional printing technology was used in thirty children with Wilms tumor (n = 13), neuroblastoma (n = 7), hepatic tumors (n = 8), retroperitoneal tumor (n = 1), and synovial sarcoma (n = 1). Among the included studies, the technology was utilized for preoperative surgical planning (five studies), improved understanding of the surgical anatomy of solid organs (two studies), and improving the parental understanding of the tumor and its management (one study). Computed tomography and magnetic resonance imaging were either performed alone or in combination for radiological evaluation in these children. Different types of printers and printing materials were used in the included studies. The cost of the 3D printed models and time involved (range 10 h to 4–5 days) were reported by two studies each. Conclusions: 3D printed models can be of great assistance to pediatric surgeons in understanding the spatial relationships of tumors with the adjacent anatomic structures. They also facilitate the understanding of families, improving doctor–patient communication.

The use of AVF.SIM system for the surgical planning of arteriovenous fistulae in routine clinical practice

Background: The number of patients treated with hemodialysis (HD) in Europe is more than half a million and this number increases annually. The arteriovenous fistula (AVF) is the vascular access (VA) of first choice, but the clinical outcome is still poor. A consistent number of AVFs fails to reach the desired blood flow rate for HD treatment, while some have too high flow and risk for cardiac complications. Despite the skill of the surgeons and the possibility to use Ultrasound investigation for mapping arm vasculature, it is still not possible to predict the blood flow volume that will be obtained after AVF maturation. Methods: We evaluated the potential of using a computational model (AVF.SIM) to predict the blood flow volume that will be achieved after AVF maturation, within a multicenter international clinical investigation aimed at assessing AVF.SIM predictive power. The study population included 231 patients, with data on AVF maturation in 124 patients, and on long-term primary patency in 180 patients. Results: At 1 year of follow-up, about 60% of AVFs were still patent, with comparable primary patency in proximal and distal anastomosis. The correlation between predicted and measured blood flow volume in the brachial artery at 40 days after surgery was statistically significant, with an overall correlation coefficient of 0.58 ( p < 0.001). The percent difference between measured and predicted brachial blood flow 40 days after surgery was less than 30% in 72% of patients investigated. Conclusions: The results indicate that the use of the AVF.SIM system allowed to predict with a good accuracy the blood flow volume achievable after VA maturation, for a given location and type of anastomosis. This information may help in AVF surgical planning, reducing the AVFs with too low or too high blood flow, thus improving AVF patency rate and clinical outcome of renal replacement therapy.

3D Patient-Specific Virtual Models for Presurgical Planning in Patients with Recto-Sigmoid Endometriosis Nodules: A Pilot Study

Background and Objective: In recent years, 3D printing has been used to support surgical planning or to guide intraoperative procedures in various surgical specialties. An improvement in surgical planning for recto-sigmoid endometriosis (RSE) excision might reduce the high complication rate related to this challenging surgery. The aim of this study was to build novel presurgical 3D models of RSE nodules from magnetic resonance imaging (MRI) and compare them with intraoperative findings. Materials and Methods: A single-center, observational, prospective, cohort, pilot study was performed by enrolling consecutive symptomatic women scheduled for minimally invasive surgery for RSE between November 2019 and June 2020 at our institution. Preoperative MRI were used for building 3D models of RSE nodules and surrounding pelvic organs. 3D models were examined during multi-disciplinary preoperative planning, focusing especially on three domains: degree of bowel stenosis, nodule’s circumferential extension, and bowel angulation induced by the RSE nodule. After surgery, the surgeon was asked to subjectively evaluate the correlation of the 3D model with the intra-operative findings and to express his evaluation as “no correlation”, “low correlation”, or “high correlation” referring to the three described domains. Results: seven women were enrolled and 3D anatomical virtual models of RSE nodules and surrounding pelvic organs were generated. In all cases, surgeons reported a subjective “high correlation” with the surgical findings. Conclusion: Presurgical 3D models could be a feasible and useful tool to support surgical planning in women with recto-sigmoidal endometriotic involvement, appearing closely related to intraoperative findings.

Is combined MDCT and echocardiography needed to guarantee accuracy in diagnosis and surgical planning of DORV and associated anomalies?

Background The term of Double-outlet right ventricle (DORV) is used to describe a spectrum of complex congenital cardiac malformations where anomalies of the ventriculo-arterial alignment are noted where both great arteries (pulmonary artery and aorta) originate completely or predominantly from the right ventricle. The purpose of this study is to evaluate the diagnostic accuracy of electrocardiography (ECG) gated multidetector computed tomography (MDCT) in preoperative assessment of DORV and its associated malformations, providing key anatomic parameters that affect surgical planning. Results A total of 50 patients diagnosed by echocardiography with DORV referred from our institute between September 2018 and August 2020 were enrolled. The location of the ventricular septal defect (VSD) to the great vessels and the alignment of the great vessels to each other as well as other associated malformations that affect the surgical planning were assessed by MDCT. The patients were retrospectively classified into subgroups according to the relative positions of the great arteries, the relationship between the great arteries and the VSD, and the presence of associated malformations according to the classification of Society of Thoracic Surgeons database. The diagnostic value of MDCT and transthoracic echocardiography (TTE) in evaluation of associated cardiac malformations apart from double outlet right ventricle was compared in 20 patients, whom surgeries were performed and surgical results were obtained. Fallot type of DORV was the most common clinical type which represented 48% of the patients in which the VSD is committed to the aorta. The second most common clinical type was Taussig–Bing anomaly which represented 30% of the patients and the VSD was seen committed to the pulmonary artery. The atrio-ventricular septal defect (AVSD)/uni-ventricular type represented 16% of the patients in the current study, with pulmonary and systemic venous anomalies, heterotaxy syndrome and situs anomalies were commonly associated. A total of 53 malformations apart from DORV were found in 20 patients whom performed surgical interventions. MDCT detected different vascular and situs anomalies in those patients with 100% sensitivity and 100% positive predictive value compared to 71.4% and 94% respectively in TTE. On the other hand, in our study TTE was superior to MDCT for detection of intracardiac anomalies with 100% sensitivity and 100% accuracy compared to 87.5% and 95% respectively in MDCT. Conclusions Our study suggested that ECG gated MDCT serves as a rapid, noninvasive imaging modality with good spatial resolution and provides excellent diagnostic image quality and has satisfactory diagnostic accuracy in the preoperative assessment of DORV. It is superior to echocardiography in providing a comprehensive mapping of the anatomy of complex anomalies especially that of extra-cardiac structures such as aorta, systemic veins, pulmonary veins, and pulmonary arteries. However, it can miss tiny intracardiac malformations. So combining the results of MDCT and echocardiography would be beneficial to guarantee the accuracy of diagnosis of DORV.