Cirugía virtual guiada para rehabilitación implantosoportada de maxilar edéntulo con carga inmediata / Virtual guided surgery for implantsupported rehabilitation of the edentulous maxilla with immediate loading

Objetivo: Presentar el relato de un caso clínico de cirugía virtual guiada para rehabilitación implantosoportada de maxilar edéntulo con carga inmediata. Relato del caso: Paciente, edéntulo total en ambos maxilares, expresó su deseo de cambiar la prótesis total superior removible por una prótesis total fija sobre implantes. Durante la evaluación clínica, se observaron condiciones biológicas favorables al tratamiento como, adecuada faja de tejido queratinizado y leve reabsorción ósea. Como tratamiento se le sugiere al paciente, una planificación inversa, asistida por cirugía virtual guiada, utilizando un prototipo de guía quirúrgica para la colocación de seis implantes dentales en el maxilar y la instalación de una prótesis protocolo de carga inmediata. Conclusiones: Los resultados nos permiten concluir que la cirugía virtual guiada por computadora para rehabilitación protésica implantosoportada de maxilar edéntulo, con carga inmediata, proporciona precisión en los procedimientos quirúrgicos, es fundamental para la confección de prótesis inmediatas, representa una alternativa mínimamente invasiva y el resultado complace a los pacientes.

Objective: present the report of a clinical case of a virtual guided surgery for implant-supported rehabilitation of the edentulous maxilla with immediate loading. Case report: Patient, bi-maxillary edentulous expressed the desire to replace the removable upper total prothesis for a total fixed prothesis on implants. During the clinical evaluation, favorable biological conditions for treatment were observed, such as adequate keratinized tissue band and mild bone resorption. As part of the treatment, the patient was recommended a reverse planning approach, assisted by virtual guided surgery. This involved a prototype surgical guide for the fixation of six dental implants in the maxilla and the installation of an immediate loading protocol prosthesis. Conclusions: The results lead us to conclude that computer-guided virtual surgery for implant-supported prosthetic rehabilitation of the edentulous maxilla with immediate loading, provides a high precision in surgical procedures. It is essential to fabrication of immediate prostheses, represents a minimally invasive alternative, and results in patient satisfaction.

Application of a computer-assisted surgery system in precision surgery of mediastinal tumors in children / 中华实用儿科临床杂志

Objective:To analyze and summarize the application and significance of the computer-assisted surgery system in precision surgery of mediastinal tumors in children.Methods:The clinical data of 54 children that underwent mediastinal tumor resection surgery in the Affiliated Hospital of Qingdao University from August 2008 to November 2021 were collected.According to whether the Hisense CAS computer-assisted surgery system was used before the operation, the patients were divided into three-dimensional (3D) reconstruction group (29 cases, 53.70%) and two-dimensional (2D) CT group (25 cases, 46.30%). The surgical indicators, postoperative hospital stay, and the incidence of surgical complications were compared between the two groups.The t-test, Mann- Whitney U test, χ2 test or Fisher′ s exact test were carried out for statistical analysis.Simulated surgery and actual surgery were compared for both 3D reconstruction and 2D CT groups. Results:There were no significant differences in gender, age, height, weight, maximum tumor diameter and tumor location between the 3D reconstruction group and 2D CT group (all P>0.05). The operation time of the 3D reconstruction group was [(125.14±41.37) min] was shorter than that of the 2D CT group [(149.24±44.53) min] ( P=0.044). The intraoperative blood loss in the 3D reconstruction group [15.00(13.50, 25.00) mL] was less than that in the 2D CT group [36.00(30.00, 75.00) mL] ( P<0.001). In addition, the indwelling time the closed thoracic drainage tube [4.00 (3.00, 5.50) d] and postoperative hospitalization days [(8.83±3.39) d] in the 3D reconstruction group were shorter than those in the 2D CT group [7.00(5.00, 11.50) d, (11.00±4.10) d] ( P=0.001, 0.038). No significant difference in postoperative complication rates was found between the 3D reconstruction group and 2D CT group ( P>0.05). The simulated operation was consistent with the actual operation in the 3D reconstruction group. Conclusions:3D reconstruction by the computer-assisted surgery system can truly reveal the anatomical relationship between tumors and surrounding organs and blood vessels, and improve the accuracy and safety of surgical resection of mediastinal tumors in children.

Application of spinal surgical robots in minimally invasive surgery for thoracolumbar fracture / 中国骨伤

OBJECTIVE@#To evaluate the safety and accuracy of Renaissance robot navigation system in minimally invasive surgery for thoracolumbar fracture.@*METHODS@#The clinical data of patients with thoracolumbar fracture who underwent posterior minimally invasive pedicle screw internal fixation from July 2016 to July 2019 was retrospectively analyzed. And the patients were divided into robot group and artificial group. Robot navigation assisted screw placement was used in robot group, and traditional unarmed screw placement was used in artificial group. There were 20 patients in robot group, including 13 males and 7 females, aged from 23 to 69 years old with an average of(45.05±11.81)years old, one case was T11 fracture, 2 cases were T12, 10 cases were L1, 6 cases were L2 and 1 case was L3. There were 20 patients in artificial group, including 11 males and 9 females, aged from 26 to 65 years old with an average of(43.40±11.22)years old, 2 cases were T11 fractures, 7 cases were T12, 10 cases were L1, and 1 case was L3. The numbers of fluoroscopy, operation time and intraoperative blood loss were observed. The screw position was evaluated by Neo method.@*RESULTS@#A total of 126 screws were implanted in robot group and 124 screws were implanted in artificial group. The operation time, fluoroscopy times, intraoperative blood loss were(115.75±14.26) min, (7.95±0.89) times and (132.50±29.36) ml in robot group and (129.50±10.50) min, (14.40±2.56) times and(182.50±23.14) ml in artificial group, respectively, there was significant difference between the groups(P<0.05). According to Neo classification method, there were 122 screws at grade 0, 4 screws at grade 1 in robot group, and there were 108 screws at grade 0, 9 screws at grade 1 and 7 screws at grade 2 in artificial group. The accuracy of the robot group was better than that of artificial group(P<0.05).@*CONCLUSION@#Compared with free hand screw placement, Renaissance robot navigation system can effectively improve the accuracy of pedicle screw placement, reduce the number of fluoroscopy times and intraoperative blood loss, thereby improving the safety of operation.

Effect of computer navigation gap balance technology on lower limb recovery after total knee arthroplasty / 中国骨伤

OBJECTIVE@#To investigate the effect of computer navigation gap balance technology on the recovery of lower limb function after total knee arthroplasty.@*METHODS@#The clinical data of 106 patients with knee osteoarthritis (OA) who underwent total knee arthroplasty from July 2018 to June 2019 were analyzed retrospectively. They were divided into measurement osteotomy group and space balance group according to different osteotomy techniques during total knee arthroplasty. There were 61 cases in osteotomy group, 24 males and 37 females;The age ranged from 45 to 77(63.35±4.26) years;According to K-L classification, 41 cases were grade Ⅲ and 20 cases were grade Ⅳ. intraoperative measurement osteotomy was performed. There were 45 cases in the gap balance group, 17 males and 28 females;Age 45 to 78(64.03±4.31) years;According to K-L classification, 29 cases were classified as grade Ⅲ and 16 cases as grade Ⅳ. computer navigation gap balance technology was implemented. The amount of intraoperative bleeding, operation time, incision length, hospital stay and postoperative complications were compared between two groups. The clinical efficacy was evaluated by Knee Society score(KSS) before operation and 12 months after operation.@*RESULTS@#Total of 106 patients were followed up for 12 to 18(20.38±3.25) months. There were significant differences in intraoperative bleeding and operation time between two groups(P<0.05). There was no significant difference in incision length and hospital stay between the two groups(P>0.05). At 12 months after operation, the total score of KSS in the gap balance group (173.59±14.50) was better than that in the osteotomy group (164.95±12.10)(P<0.05). There were no serious complications of poor prosthesis loosening between two groups during follow-up, and there was no significant difference in the incidence of other complications between two groups(P>0.05).@*CONCLUSION@#The application of computer navigation gap balance technology in total knee arthroplasty is conducive to the recovery of lower limb function in patients with OA, and there are no serious adverse complications and high safety.

Comparison of alignment and operative time between portable accelerometer-based navigation device and computer assisted surgery in total knee arthroplasty / 北京大学学报(医学版)

OBJECTIVE@#To explore the differences of alignment and operative time between portable accelerometer-based navigation device (PAD) and computer assisted surgery (CAS) in total knee arthroplasty (TKA).@*METHODS@#Data of patients using iASSIST (a kind of PAD) and OrthoPilot (a kind of CAS) for TKA in Peking University Third Hospital from December 2017 to December 2019 were retrospectively collected. The differences of preoperative general data, preoperative alignment, operative time and postoperative alignment were studied between the two groups.@*RESULTS@#A total of 82 patients were enrolled in our study, including 40 patients in the PAD group and 42 patients in the CAS group. Gender, age, body mass index (BMI), surgical side, preoperative hip-knee-ankle (HKA) angle and preoperative HKA angle deviation didn't show statistically significant difference between the PAD group and the CAS group (P>0.05). Postoperative HKA angle (180.8°±2.2° vs.181.8±1.6°, t=－2.458, P=0.016) and postoperative coronal femoral-component angle (CFA, 90.6°±1.8° vs. 91.6°±1.6°, t =－2.749, P=0.007) of the PAD group were smaller than those of the CAS group, but there was no significant difference in coronal tibia-component angle (CTA, 90.0°±1.3° vs.89.6°±1.4°, t=1.335, P=0.186) between the two groups. There was no significant difference in the rate of outliers (varus or valgus > 3°) for postoperative HKA angle (10.0% vs.11.9%, χ2 =0.076, P=0.783), CFA (12.5% vs. 14.3%, χ2=0.056, P=0.813) and CTA (2.5% vs. 0%, χ2=1.063, P=0.303). There was no significant difference in the accuracy of postoperative HKA angle (2.1° vs. 2.0°, t=0.055, P=0.956), CFA (1.4° vs. 1.8°, t=－1.365, P=0.176) and CTA (1.0° vs. 1.1°, t=－0.828, P=0.410) between the two groups. The precision of postoperative HKA angle (1.1° vs. 1.3°, F=1.251, P=0.267), CFA (1.3° vs. 1.4°, F=0.817, P=0.369) and CTA (0.8° vs. 0.9°, F=0.937, P=0.336) were also not significantly different. We also didn't find statistically significant difference in operative time between the two groups [(83.4±25.6) min vs. (86.5±17.7) min, t=－0.641, P=0.524].@*CONCLUSION@#PAD and CAS had similar accuracy and precision in alignment in TKA, and there was no significant difference in operative time, which indicates that PAD has a broad application prospect in TKA.

Application of computer navigation technique in the treatment of complex orbital fractures / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To evaluate the efficacy and utility of computer navigation technique in the treatment of complex orbital fracture.<p>METHODS: A retrospective review of 19 patients with complex orbital fractures were conducted. They underwent the reconstructive surgery assisted by image-data-based computer navigation. The pre- and postoperative data of enophthalmos, eyeball movement, diplopia, infraorbital numbness, and orbit CT image were recorded and analyzed. <p>RESULTS: The processes of pre-operation planning and intraoperative navigation were successful. During the 6 to 18mo postoperative follow-up, enophthalmos was completely corrected in 14 cases, while 5 patients had slight residual enophthalmos. Eyeball movement restriction was completely corrected in 7 cases, and was also improved in 3 cases. Diplopia was disappeared in 10 patients and improved in 2 patients, but still maintained in 1 patient postoperatively. Infraobital numbness was found in 4 cases, and dissappeared in 6mo postoperatively. No serious complications such as optic nerve lesion and vision loss were observed. Postoperative CT scans demonstrated that the fractures were corrected in all cases. The accuracies of the surgeries were satisfying. <p>CONCLUSION: Computer navigation system is a safe and effictive technique in assisting diorthosis in complex orbital fracture.

Augmented reality in plastic surgery: recent applications and developments / 中华整形外科杂志

Augmented reality(AR)is a technique that superimposes continuous computer-generated images onto real scenes. With the collaborative work of tracking module, registration module and display module, real-time fused images can be composed and shown. In recent years, AR has been applied in several medical fields, such as medical education, remote medical aid, navigation system, etc.Latest applications and developments of AR in plastic surgery was reviewed in this article.

Utilization of Spinal Navigation to Facilitate Hassle-Free Rod Placement during Minimally-Invasive Long-Construct Posterior Instrumentation

During minimally-invasive long-construct posterior instrumentation, it may be challenging to contour and place the rod as the screw heads are not visualized. To overcome this, we utilized the image data merging (IDM) facility of our spinal navigation system to visualize a coherent whole image of the construct throughout the procedure. Here, we describe this technique that was used for a patient in whom L1–L5 posterior instrumentation was performed. Using an IDM facility, screws are color coded and after placement, the final image is saved. Saved images of all previous screws are displayed and observed while placing the subsequent screws. Therefore, the entry point, depth, and mediolateral alignment of subsequent screws can be adjusted to fall in line with previous screws such that the rod can be placed without hassle. Moreover, final adjustments to the construct are kept to a minimum. The possibility of screw pullout due to force engaging the rod on poorly aligned screws is thus avoided.

Navigated versus Conventional Technique in High Tibial Osteotomy: A Meta-Analysis Focusing on Weight Bearing Effect

PURPOSE: We aimed to determine whether navigated opening wedge high tibial osteotomy (HTO) is superior to the conventional technique in terms of accuracy of the coronal and sagittal alignment correction, functional outcome, and operative time. METHODS: Studies comparing navigated and conventional HTO were included in this meta-analysis. We compared the incidence of radiological outliers in coronal alignment and tibial slope maintenance, mean differences in functional outcome scales, and operative time. Subgroup analyses were performed on coronal alignment accuracy based on the intraoperative method of alignment confirmation: fluoroscopy vs. gap measurement method. RESULTS: Twelve studies were included: there were 434 knees in the navigated HTO studies and 405 knees in the conventional HTO studies. The risk of outlier was lower in navigated HTO than in conventional HTO; however, the difference was not significant when navigated HTO was compared with conventional HTO performed using the gap measurement method. Tibial slope maintenance was comparable or better in navigated HTO. No difference was found in the American Knee Society function and Lysholm scores. Navigated HTO necessitated a longer operative time of approximately 10 minutes. CONCLUSIONS: The use of navigation in HTO can improve accuracy in both coronal and sagittal alignments, but its clinical benefit is unclear.

CT-based Navigation System Using a Patient-Specific Instrument for Femoral Component Positioning: An Experimental in vitro Study with a Sawbone Model

PURPOSE: The intraoperative version of the femoral component is usually determined by visual appraisal of the stem position relative to the distal femoral condylar axis. However, several studies have suggested that a surgeon's visual assessment of the stem position has a high probability of misinterpretation. We developed a computed tomography (CT)-based navigation system with a patient-specific instrument (PSI) capable of three-dimensional (3D) printing and investigated its accuracy and consistency in comparison to the conventional technique of visual assessment of the stem position. MATERIALS AND METHODS: A CT scan of a femur sawbone model was performed, and pre-experimental planning was completed. We conducted 30 femoral neck osteotomies using the conventional technique and another 30 femoral neck osteotomies using the proposed technique. The femoral medullary canals were identified in both groups using a box chisel. RESULTS: For the absolute deviation between the measured and planned values, the mean two-dimensional anteversions of the proposed and conventional techniques were 1.41° and 4.78°, while their mean 3D anteversions were 1.15° and 3.31°. The mean θ 1, θ 2, θ 3, and d, all of which are parameters for evaluating femoral neck osteotomy, were 2.93°, 1.96°, 5.29°, and 0.48 mm for the proposed technique and 4.26°, 3.17°, 4.43°, and 3.15 mm for the conventional technique, respectively. CONCLUSION: The CT-based navigation system with PSI was more accurate and consistent than the conventional technique for assessment of stem position. Therefore, it can be used to reduce the frequency of incorrect assessments of the stem position among surgeons and to help with accurate determination of stem anteversion.

The accuracy of a 3D printing surgical guide determined by CBCT and model analysis

PURPOSE: The aim of this clinical study was to assess the accuracy of the implants placed using a universal digital surgical guide. MATERIALS AND METHODS: Among 17 patients, 28 posterior implants were included in this study. The digital image of the soft tissue acquired from cast scan and hard tissue from CBCT have been superimposed and planned the location, length, diameter of the implant fixture. Then digital surgical guides were created using 3D printer. Each of angle deviations, coronal, apical, depth deviations of planned and actually placed implants were calculated using CBCT scans and casts. To compare implant positioning errors by CBCT scans and plaster casts, data were analyzed with independent samples t-test. RESULTS: The results of the implant positioning errors calculated by CBCT and casts were as follows. The means for CBCT analyses were: angle deviation: 4.74 ± 2.06°, coronal deviation: 1.37 ± 0.80 mm, and apical deviation: 1.77 ± 0.86 mm. The means for cast analyses were: angle deviation: 2.43 ± 1.13°, coronal deviation: 0.82 ± 0.44 mm, apical deviation: 1.19 ± 0.46 mm, and depth deviation: 0.03 ± 0.65 mm. There were statistically significant differences between the deviations of CBCT scans and cast. CONCLUSION: The model analysis showed lower deviation value comparing the CBCT analysis. The angle and length deviation value of the universal digital guide stent were accepted clinically.

Reliability and Validity of the Femorotibial Mechanical Axis Angle in Primary Total Knee Arthroplasty: Navigation versus Weight Bearing or Supine Whole Leg Radiographs

PURPOSE: To evaluate the reliability and validity of the femorotibial mechanical axis angle from radiographs in the weight bearing (WB) and supine positions compared with navigation-measured values. MATERIALS AND METHODS: Sixty-eight cases of navigation-assisted total knee arthroplasty (TKA) were included. The pre- and postoperative whole leg radiographs (WLRs) in WB and supine positions were compared with the initial and final navigation values. RESULTS: The mean mechanical axis angle from the preoperative WBWLR and navigation were not statistically different (p=0.079) and were correlated strongly with each other (intraclass correlation [ICC], 0.818). However, on postoperative measurements, although the WBWLR and navigation values were not different (p=0.098), they were not correlated with each other (ICC, 0.093). The standard error of measurement was 1.8°±3.6° for the preoperative WBWLR and 2.5°±4.8° for the postoperative WBWLR. The validity that was determined by the Bland-Altman plot was not acceptable for both pre- and postoperative measurements. CONCLUSIONS: The preoperative WBWLR could provide accurate but not precise measurement value of the femorotibial mechanical axis angle for navigation-assisted TKA, and postoperative measurements in navigation were not comparable with radiographic measurements. The lack of agreement was found between the radiographic and navigation measurements of the coronal alignment regardless of pre- or postoperative evaluation although the accuracy was found acceptable. LEVEL OF EVIDENCE: Level 4

Osteoma osteoide de cuello femoral: A propósito de un caso / Femoral neck osteoid osteoma: about a case

El osteoma osteoide es un tumor óseo benigno, de pequeño tamaño, sin potencial de crecimiento. Habitualmente se considera a los tumores óseos benignos y malignos como una causa poco frecuente de cojera en apirexia, siendo más frecuentes las patologías inflamatorias inespecíficas como la sinovitis transitoria de cadera, la enfermedad de Perthes y la condropatía conjugal del adolescente. Se presenta el caso clínico de un escolar de 8 años con una cojera dolorosa en apirexia de 4 meses de evolución con sospecha imagenológica de osteoma osteoide de cuello de fémur. Se decide realizar prueba terapéutica con ácido acetilsalicílico. A las 24 horas el niño se encontraba asintomático. Se indicó procedimiento quirúrgico de resección mediante punción bajo tomografía axial computada. El diagnóstico se confirmó mediante anatomía patológica. Se realizó resección completa del tumor con buena evolución. Es importante desde el punto de vista pediátrico realizar un correcto diagnóstico diferencial entre las diferentes causas de cojera dolorosa en apirexia, basándonos en la historia clínica y la imagenología.

Osteoid osteomas are small benign bone tumors which lack growth potential. All bone tumors, whether benign or malign, are considered a rare cause of apyretic limping, being non-specific inflammatory diseases more frequent, such as transient synovitis of the hip, Perthes disease and adolescent conjugal chondropathy. The study presents the clinical case of an 8 year old school boy with a 4 month evolution painful apyretic limp, being there a suspicion of femoral neck osteoid osteoma according to imaging studies. Therapeutic trial of acetylsalicylic acid was performed. Twenty four hours later the boy was asymptomatic. A tomography-guided puncture was indicated. Clinical diagnosis was pathologically confirmed. Subsequently, complete surgical resection of the tumor was performed, the evolution being favorable. From a pediatric perspective it is important to make an accurate differential diagnosis between the different possible causes of painful apyretic limp, based on clinical history and imaging studies.

Fluxo de trabalho para aplicação da técnica de cirurgia guiada em reabilitação total de maxila / Workflow for guided implant surgery (GIS) in full arch maxillary rehabilitation

A aplicação de um fluxo digital é um recurso cada vez mais utilizado na Implantodontia. A técnica de cirurgia guiada tem evoluído constantemente, acompanhando os avanços de hardwares e softwares aplicados na Odontologia, resultando no aumento da indicação e precisão dos guias cirúrgicos obtidos. O objetivo deste trabalho foi, através de um relato de caso clínico, demonstrar o fluxo de trabalho utilizado para aplicação da técnica de cirurgia guiada em reabilitação total de maxila, utilizando o software coDiagnostiX (Dental Wings, Chemnitz, Alemanha). Após as etapas de preparo pré-tomográfico, obtenção da digitalização de superfície, aquisições tomográficas e planejamento virtual, foram instalados seis implantes cone-morse (Neodent, Curitiba, Brasil), com a utilização de um guia cirúrgico obtido por impressão 3D. Após o período de osseointegração, foi instalada uma prótese fixa implantossuportada. O planejamento virtual em software específico, através da digitalização de superfície associada à tomografia computadorizada de feixe cônico (TCFC), propõe um diagnóstico previsível, seguro e a possibilidade de oferecer maior segurança e precisão nas reabilitações com implantes osseointegrados.

The application of a digital workflow is an increasingly used resource in Implantology. The guided implant surgery (GIS) has constantly evolved, following the advances of hardware and software applied in Dentistry, resulting in an increase in the indication and precision of the surgical guides. The objective of this article is, through a clinical case report, to demonstrate a workflow used to apply guided surgery technique in full-arch maxillary rehabilitation using the coDiagnostiX software (Dental Wings, Chemnitz, Germany). After the pre-tomographic preparation, surface scanning, tomographic acquisitions and virtual planning, six morse taper implants (Neodent, Curitiba, Brazil) were placed using a surgical guide obtained by 3D printing. After a period of osseointegration, a implant supported fixed prosthesis was placed. The virtual planning in specific software, through surface scanning associated with cone beam computed tomography (CBCT), proposes a predictable, safe diagnosis and the possibility of offering greater safety and precision in the rehabilitations with osseointegrated implants.

A classification of types of hepatic vein based on data obtained from a computer-assisted surgery system and its clinical implications in liver surgery / 中华肝胆外科杂志

Objective To classify the types of hepatic vein and to measure their corresponding liver venous drainage volumes based on analysis of data obtained from a computer-assisted surgery system with an aim to provide an anatomical basis on individualized anatomical hepatectomy.Methods Thin-layer computed tomography (CT) imaging on 570 patients were reconstructed using the Hisense CAS.The types of hepatic vein were classified according to their anatomical variations.The margins of the hemilivers or sectors and their corresponding hepatic venous drainage volumes were displayed.Results The major hepatic veins were classified into three types:Type Ⅰ (270/570,47.4％),type Ⅱ (294/570,51.6％),and type Ⅲ (6/570,1.0％).The left hepatic vein (LHV) was classified as type Ⅰ in 190/570 (33.3％),type Ⅱ in 79/570 (13.9％),and type Ⅲ in 301/570 (52.8％).The middle hepatic vein (MHV) was classified as type Ⅰ in313/570 (54.9％),type Ⅱ in 174/570 (30.5％),and type Ⅲ in 83/570 (14.6％).The right hepatic vein (RHV) was classified as type Ⅰ in 456/570 (80.0％),type Ⅱ in 79/570 (13.9％),and type Ⅲ in 35/570 (6.1％).Type Ⅰ was further classified into four subtypes of A (26/456,5.7％),B (404/456,88.6％),C (20/456,4.4％),and D (6/456,1.3％).The LHV volume was (25.0± 6.6) ％,the MHV volume was (34.8 ± 9.5) ％ and the RHV volume was (25.1 ± 11.6) ％ in 63 patients with inferior right hepatic veins (IRHV).The IRHV and other branches volumes were (14.7 ± 7.4) ％.The RHV volume was (40.7 ± 8.6) ％ in 68 patients without IRHV.Conclusions Hepatic venous variations are complex.Significant differences existed in the hepatic venous drainage volumes.The Hisense CAS clearly delineated the relationship between the intrahepatic vascular structures and the liver carcinoma which hopefully can lead to improvement in the success rate of complex hepatectomy.

A classification of types of hepatic vein based on data obtained from a computer-assisted surgery system and its clinical implications in liver surgery / 中华肝胆外科杂志

Objective To classify the types of hepatic vein and to measure their corresponding liver venous drainage volumes based on analysis of data obtained from a computer-assisted surgery system with an aim to provide an anatomical basis on individualized anatomical hepatectomy.Methods Thin-layer computed tomography (CT) imaging on 570 patients were reconstructed using the Hisense CAS.The types of hepatic vein were classified according to their anatomical variations.The margins of the hemilivers or sectors and their corresponding hepatic venous drainage volumes were displayed.Results The major hepatic veins were classified into three types:Type Ⅰ (270/570,47.4％),type Ⅱ (294/570,51.6％),and type Ⅲ (6/570,1.0％).The left hepatic vein (LHV) was classified as type Ⅰ in 190/570 (33.3％),type Ⅱ in 79/570 (13.9％),and type Ⅲ in 301/570 (52.8％).The middle hepatic vein (MHV) was classified as type Ⅰ in313/570 (54.9％),type Ⅱ in 174/570 (30.5％),and type Ⅲ in 83/570 (14.6％).The right hepatic vein (RHV) was classified as type Ⅰ in 456/570 (80.0％),type Ⅱ in 79/570 (13.9％),and type Ⅲ in 35/570 (6.1％).Type Ⅰ was further classified into four subtypes of A (26/456,5.7％),B (404/456,88.6％),C (20/456,4.4％),and D (6/456,1.3％).The LHV volume was (25.0± 6.6) ％,the MHV volume was (34.8 ± 9.5) ％ and the RHV volume was (25.1 ± 11.6) ％ in 63 patients with inferior right hepatic veins (IRHV).The IRHV and other branches volumes were (14.7 ± 7.4) ％.The RHV volume was (40.7 ± 8.6) ％ in 68 patients without IRHV.Conclusions Hepatic venous variations are complex.Significant differences existed in the hepatic venous drainage volumes.The Hisense CAS clearly delineated the relationship between the intrahepatic vascular structures and the liver carcinoma which hopefully can lead to improvement in the success rate of complex hepatectomy.

Clinical analysis of mandibular reconstructions using synthetic bones based on three-dimensional printing technology in 149 cases / 上海交通大学学报（医学版）

Objective-To assess the clinical value of the computer-assisted three-dimensional reconstruction technique design and evaluate the climcal experience of manufacture artificial bone precision to repair the mandibular defect.Methods· From 2001 to 2016,163 computer-assisted reconstruction surgeries had been performed in Craniofacial Department,Ninth People's Hospital,Shanghai Jiao Tong University School of Medicine.During six months followup,the measurement data was conducted and compared with three-dimensional CT result.Random measurement of the three key anatomical points pre-and post-operative carried out with statistical error was used to evaluate the accuracy of computer-assisted three-dimensional reconstruction in mandibular defects repairation and to investigate the clinical application value of the operation time and postoperative complication rate.Results· From July 2001 to July 2016,a total of 163 patients underwent computer-assisted three-dimensional reconstruction of artificial bone repair for mandibular defects;149 patients met the statistical criteria in which preoperative design and postoperative actual effect's average distance error (1.27±0.15) mm,operation time (2.5±1.2) h.Conclusion· Threedimensional design of artificial bone to repair the mandibular defect is a valuable technology,by relying on quantitative design and preoperative simulation to simplify the difficulty and improve the accuracy of surgery.The patients showed high satisfaction rate with low surgical complications and long-term efficacy.

The Effect of Sagittal Knee Deformity on Preoperative Measurement of Coronal Mechanical Alignment during Total Knee Arthroplasty

PURPOSE: The purpose of this prospective study was to determine correlation between coronal mechanical alignment measured on preoperative standing full-length radiographs and navigation during total knee arthroplasty (TKA) in the presence of an associated sagittal deformity (hyperextension and flexion deformity). MATERIALS AND METHODS: Coronal mechanical alignment measured on preoperative, standing, full-length, hip-to-ankle anteroposterior radiographs was compared with intraoperative measurements recorded with computer navigation in 200 primary navigated TKAs. RESULTS: The mean difference in mechanical alignment between the two techniques was significantly greater (p=0.001) in patients with an associated flexion deformity >10° when compared to knees with associated flexion deformity ≤10°; 48% of knees with a flexion deformity >10° had a difference of ≥3° between the full-length radiograph and navigation alignment measurements. There was a strong correlation between the radiographic and navigation measurement techniques. CONCLUSIONS: The mean difference in coronal mechanical alignment between the two techniques was significantly higher in patients with an associated flexion deformity >10°. Hence, surgeons should take caution when relying on preoperative full-length radiographs for determining coronal mechanical alignment in patients with an associated flexion deformity >10° where using navigation may be more reliable.

The application and development of dynamic navigation system in implant dentistry / 口腔疾病防治

@#Dynamic surgical navigation system has been wildly used in implantology, the navigation surgical system provide preoperative trajectory planning. Moreover, the constant visualization of drilling trajectory during operation assist the operators by avoiding critical anatomic structures to achieve safer surgery. Our article focuses on the development and function of dynamic navigation system to evaluate the accuracy of dynamic surgical navigation system when used for regular implants and zygomatic implants placement. We aim to discuss the accuracy of different brand of dynamic surgical navigation systems for implants placement and to investigate the main reasons led the inaccurate outcome.

Cirugía asistida por computador en tumores óseos: principios generales / Computer assisted surgery in bone tumours: general principles

La mayoría de los tumores óseos primarios pueden ser tratados mediante una resección amplia —muchas veces asociada a terapias adyuvantes— sin comprometer la sobrevida del paciente. La posibilidad de una resección conservadora depende de la localización y tamaño del tumor y de las partes blandas circundantes. Una cuidadosa evaluación de estudios imagenológicos permite al cirujano elaborar un plan quirúrgico que permita una resección con márgenes adecuados, al mismo tiempo que conservar la mayor cantidad de tejido sano, de modo de obtener una extremidad funcional. A veces, la ejecución quirúrgica de lo planeado se hace muy difícil, y la precisión de esta puede resultar afectada. La cirugía guiada por computador se ha constituido en una herramienta útil en estas situaciones. Está basada en la creación de un plan virtual en 3 dimensiones mediante el procesamiento de imágenes de tomografía computada (TC) y resonancia nuclear magnética (RNM). Este plan puede ser reproducido en el escenario quirúrgico mediante la correspondencia entre este escenario virtual y la anatomía real del paciente. Esta tecnología puede permitir una mayor precisión en la ejecución de osteotomías en zonas difíciles como la pelvis, minimizando la resección innecesaria de tejido sano, pero manteniendo un margen oncológico adecuado. Describiremos los principios y el razonamiento que fundamentan el uso de la cirugía guiada por computador en la cirugía de tumores óseos, la cual se ha constituido en una herramienta útil para el manejo de situaciones clínicas específicas...

The majority of primary bone tumours can be effectively treated with wide resection —frequently associated with adjuvant therapy— without compromising the outcome of the patient. The feasibility of limb-sparing surgery in a particular scenario is dependent on the location and size of the tumour, as well as the involvement of the host bone and surrounding soft tissues. Careful evaluation of imaging studies allows the surgeon to plan the resection with adequate margins, while preserving as much normal tissues as possible, in order to achieve a functional limb. At times, the surgical execution of what was planned as resection becomes very difficult, and precision may be less than optimal. Computer-guided surgery has become a useful tool in these situations. It is based on the creation of a three-dimensional virtual plan by means of image processing from computed tomography (CT) and magnetic resonance (MRI) of the clinical situation. This plan is reproduced in the surgical field by means of the interaction between this virtual scenario and the actual anatomy of the patient. This technology could allow better precision in the execution of osteotomies in difficult areas, such as the pelvis, minimising unnecessary resection of normal tissue, while maintaining wide margins. A description is presented of the principles and rationale of computer-guided surgery for bone tumours, which has become a useful tool for the management of selected clinical situations...