Three-dimensional Image Fusion Research Articles

Mixed reality combined with surgical navigation technology assisted in parapharyngeal space tumors surgery: a clinical study

Objective: To assess the feasibility and application of mixed reality combined with surgical navigation technology in parapharyngeal space tumor surgery, and to provide a reference for the development and promotion of this technology. Methods: In this study, retrospective data collection was conducted on 16 patients with parapharyngeal space tumors who were treated at the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology from June 2020 to June 2023. The patient's age was (39.6±17.8) years, with 4 males and 12 females. Mixed reality combined with surgical navigation technology was utilized to assist physicians in the treatment of these patients. Mixed reality combined with surgical navigation technology was used to assist physicians in treatment of these patients. The application steps included acquisition of image data, processing of image data [three-dimensional (3D) reconstruction, image fusion, and virtual surgical design], development of surgical navigation plan, connection of mixed reality and navigation system, automatic registration and intraoperative guidance and validation. In the preoperative plan, landmark points were placed on the virtual tumor and surrounding important structures reconstructed using digital software, serving to guide the localization of crucial anatomical structures. Intraoperative positioning deviation, surgical time, intraoperative blood loss, and postoperative complications were recorded and analyzed to evaluate the clinical application effectiveness of mixed reality combined with surgical navigation technology. Results: With the assistance of mixed reality combined with surgical navigation technology, 16 patients successfully underwent tumor resection. All patients were accurately diagnosed preoperatively by 3D reconstruction and image fusion technology, and a comprehensive preoperative plan was formulated; intraoperatively, mixed reality combined with surgical navigation technology was utilized for the localization of important structures. The average localization deviation of 38 landmark points during the operation were (4.43±1.96) mm, with 62% (26/42) of the points having a deviation of ≥0 and<5 mm. The average duration of the operation was (149.6±53.9) min and the blood loss was 70 (45, 150) ml. The average postoperative follow-up was 16 months, and five patients experienced postoperative complications involving facial paralysis, hoarseness, and choking. Conclusions: Mixed reality combined with surgical navigation technology can achieve the three-dimensional visualization of oral and maxillofacial anatomical structures to achieve precise preoperative diagnosis. During surgery, the technology can real-time display the relationship between soft tissue tumors and the surrounding important anatomical structures, guide surgical operation, and enhance the safety of surgery.

Three-dimensional fusion imaging to assess apposition of low-profile visualized intraluminal support stent for intracranial aneurysm coiling

ObjectiveTo investigate on three-dimensional (3D) fusion images the apposition of low-profile visualized intraluminal support (LVIS) stents in intracranial aneurysms after treatment and assess inter-rater reliability. Materials and methodsRecords of all patients with unruptured intracranial aneurysms who were treated with the LVIS stent were retrospectively accessed and included in this study. Two neurosurgeons evaluated the presence of malapposition between the vessel walls and the stent trunk (crescent sign) and the vessel wall and the stent edges (edge malappostion) on 3D fusion images. These images were high-resolution cone-beam computed tomography images of the LVIS stent fused with 3D-digital subtraction angiography images of the vessels. Associations between malapposition and aneurysm location were assessed by Fisher's exact test, and inter-rater agreement was estimated using Cohen's kappa statistic. ResultsForty consecutive patients were included. In all patients, 3D fusion imaging successfully visualized the tantalum helical strands and the closed-cell structure of the nitinol material of the low-profile visualized intraluminal support. A crescent sign was observed in 27.5 % and edge malapposition in 47.5 % of the patients. Malapposition was not significantly associated with location (p = 0.23 crescent sign, p = 0.07 edge malapposition). Almost perfect (κ = 0.88) and substantial (κ = 0.76) agreements between the two raters were found for the detection of crescent signs and edge appositions, respectively. Conclusions3D fusion imaging provided clear visualization of the LVIS stent and parent arteries, and could detect malapposition with excellent inter-rater reliability. This technique may provide valuable guidance for surgeons in determining postoperative management.

Usefulness of Preoperative Simulation: Skull Base Approach

Preoperative simulation images creates an accurate visualization of a surgical field. The anatomical relationship of the cranial nerves, arteries, brainstem, and related bony protrusions is important in skull base surgery. However, an operator's intention is unclear for a less experienced neurosurgeon. Three-dimensional(3D)fusion images of computed tomography and magnetic resonance imaging created using a workstation aids precise surgical planning and safety management. Since the simulation images allows to perform virtual surgery, a déjà vu effect for the surgeon can be obtained. Additionally, since 3D surgical images can be used for preoperative consideration and postoperative verification, discussion among the team members is effective from the perspective of surgical education for residents and medical students. Significance of preoperative simulation images will increase eventually.

Fusion imaging for guidance of pulmonary arteriovenous malformation embolisation with minimal radiation and contrast exposure.

Hereditary haemorrhagic telangiectasia is an inherited disorder characterised by vascular dysplasia that leads to the development of arteriovenous malformations. Pulmonary arteriovenous malformations occur in approximately 30% of patients with haemorrhagic telangiectasia. Given the complex characteristics of haemorrhagic telangiectasia lesions, the application of three-dimensional fusion imaging holds significant promise for procedural guidance and decrease in contrast and radiation dosing. We reviewed all patients who underwent transcatheter approach for pulmonary arteriovenous malformation occlusion with fusion image guidance from June 2018 to September 2023 from a single centre. A total of nine cases with haemorrhagic telangiectasia and transcatheter occlusion of pulmonary arteriovenous malformations using fusion imaging were identified. Five (56%) were male, mean age at procedure was 15.7 years (10-28 years) and mean number of pulmonary arteriovenous malformations intervened was three per patient (1-7). Two of the cases were complex repeat embolisations. The mean fluoroscopy time was 40.6 min (10.7-68.8 min), with mean contrast dose of 28.8 mL (11-60 mL; mean of 0.51 mL/kg) and mean radiation dose of 66.3 mGy (25.6-140 mGy; mean of 40.5 mGy/m2). There were no complications reported during the procedures, with no additional interventions necessary. Fusion imaging in pulmonary arteriovenous malformations embolisation for patients with haemorrhagic telangiectasia is feasible and has the potential to reduce contrast and radiation doses. To our knowledge, we describe the lowest radiation and contrast doses per patient using fusion imaging technology reported in the literature to date.

Use of indocyanine green angiography during endoscopic microvascular decompression for trigeminal neuralgia

BackgroundThe aim of this study was to assess the efficacy of indocyanine green (ICG) angiography during full endoscopic microvascular decompression for trigeminal neuralgia. MethodsWe extracted retrospective data of patients who received ICG videoangiography during full endoscopic microvascular decompression for trigeminal neuralgia. Preoperative neurovascular contact was evaluated by three-dimensional (3D) fusion images using image analysis software Ziostation2 (ZIOSOFT, Tokyo, Japan) and Intraoperative ICG angiography was used in pre and post ICG injection to identify and assess blood flow in the offending vessel for adequate transposition planification and assess for immediate post transposition blood flow or vasospasm respectively. Patients were assessed the next morning for early signs of brainstem infarction and at one month follow up. ResultsThere were 44 patients. All patients had ICG videoangiography done during the procedure. The mean age was 65.5 and male female ratio 3.4:1. Some anatomical variants were identified during this procedure. Five patients (11.3%) had a trigeminocerebellar artery, three patients (6.8%) had a developed superior petrosal vein and one patient (2.2%) had dural adhesions with encasement of anterior inferior cerebellar artery. Among the 44 patients enrolled, 34 had transposition done and 10 had combined transposition either with neurolysis or Teflon interposition. The main offending vessel was Superior cerebellar artery (SCA) in 23 patients (67.6%). In 5 (14.7%) of 34 patients who underwent Transposition, vasospasm was seen and no complications were observed in all patients but 93.1% had good pain control in postoperative. ConclusionICG angiography in endoscopic microvascular decompression is safe and effective in depicting the offending vessel, its branches and some perforators and contributes significantly to the determination of treatment strategy.

Precise localization of microvascular invasion in hepatocellular carcinoma based on three-dimensional histology-MR image fusion: an ex vivo experimental study.

Microvascular invasion (MVI) is an independent risk factor for postoperative recurrence of hepatocellular carcinoma (HCC). However, MVI cannot be detected by conventional imaging. To localize MVI precisely on magnetic resonance (MR) images, we evaluated the feasibility and accuracy of 3-dimensional (3D) histology-MR image fusion of the liver. Animal models of VX2 liver tumors were established in 10 New Zealand white rabbits under ultrasonographic guidance. The whole liver lobe containing the VX2 tumor was extracted and divided into 4 specimens, for a total of 40 specimens. MR images were obtained with a T2-weighted sequence for each specimen, and then histological images were obtained by intermittent, serial pathological sections. 3D histology-MR image fusion was performed via landmark registration in 3D Slicer software. We calculated the success rate and registration errors of image fusion, and then we located the MVI on MR images. Regarding influencing factors, we evaluated the uniformity of tissue thickness after sampling and the uniformity of tissue shrinkage after dehydration. The VX2 liver tumor model was successfully established in the 10 rabbits. The incidence of MVI was 80% (8/10). 3D histology-MR image fusion was successfully performed in the 39 specimens, and the success rate was 97.5% (39/40). The average registration error was 0.44±0.15 mm. MVI was detected in 20 of the 39 successfully registered specimens, resulting in a total of 166 MVI lesions. The specific location of all MVI lesions was accurately identified on MR images using 3D histology-MR image fusion. All MVI lesions showed as slightly hyperintense on the high-resolution MR T2-weighted images. The results of the influencing factor assessment showed that the tissue thickness was uniform after sampling (P=0.38), but the rates of the tissue shrinkage was inconsistent after dehydration (P<0.001). 3D histology-MR image fusion of the isolated liver tumor model is feasible and accurate and allows for the successful identification of the specific location of MVI on MR images.

Utilization of three-dimensional fusion images with high-resolution computed tomography angiography for preoperative evaluation of microvascular decompression: patient series.

High-resolution computed tomography (CT), outfitted with a 0.25-mm detector, has superior capability for identifying microscopic anatomical structures compared to conventional CT. This study describes the use of high-resolution computed tomography angiography (CTA) for preoperative microvascular decompression (MVD) assessment and explores the potential effectiveness of three-dimensional (3D) image fusion with magnetic resonance imaging (MRI) by comparing it with traditional imaging methods. Four patients who had undergone preoperative high-resolution CTA and MRI for MVD at Osaka University Hospital between December 2020 and March 2022 were included in this study. The 3D-reconstructed images and intraoperative findings were compared. One patient underwent conventional CTA, thus allowing for a comparison between high-resolution and conventional CTA in terms of radiation exposure and vascular delineation. Preoperative simulations reflected the intraoperative findings for all cases; small vessel compression of the nerve was identified preoperatively in two cases. Compared with conventional CTA, high-resolution CTA showed superior vascular delineation with no significant change in radiation exposure. The use of high-resolution CTA with reconstructed 3D fusion images can help to simulate prior MVD. Knowing the location of the nerves and blood vessels can perioperatively guide neurosurgeons.

Three-dimensional fusion images from digital subtraction angiography for the treatment of direct carotid-cavernous fistulas: illustrative case.

Direct carotid-cavernous fistulas (dCCFs) are often treated endovascularly. However, because the dCCF is usually a high-flow shunt, it is often difficult to obtain an accurate vascular structure using conventional digital subtraction angiography (DSA). Here, the authors report a case of successfully treated dCCF using three-dimensional (3D) fused DSA images. The patient presented with tinnitus, followed by oculomotor palsy, prompting magnetic resonance imaging that indicated a dural arteriovenous fistula of the cavernous sinus. DSA was performed before treatment, and a diagnosis of dCCF due to a ruptured aneurysm was made. In this case, the 3D fused simulation images enabled the authors to obtain an accurate vascular structure, resulting in successful coil embolization. Three-dimensional fusion images from DSA provide detailed anatomical information and are useful for treating high-flow dCCFs.

Cloud-based fusion imaging improves operative metrics during fenestrated endovascular aneurysm repair

ObjectiveEndovascular treatment of complex aortic pathology has been associated with increases in procedural-related metrics, including the operative time and radiation exposure. Three-dimensional fusion imaging technology has decreased the radiation dose and iodinated contrast use during endovascular aneurysm repair. The aim of the present study was to report our institutional experience with the use of a cloud-based fusion imaging platform during fenestrated endovascular aneurysm repair (FEVAR). MethodsA retrospective review of a prospectively maintained aortic database was performed to identify all patients who had undergone FEVAR with commercially available devices (Zenith Fenestrated; Cook Medical Inc, Bloomington, IN) between 2013 and 2020 and all endovascular aneurysm repairs performed using Cydar EV Intelligent Maps (Cydar Medical, Cambridge, UK). The Cydar EV cohort was reviewed further to select all FEVARs performed with overlay map guidance. The patient demographic, clinical, and procedure metrics were analyzed, with a comparative analysis of FEVAR performed without and with the Cydar EV imaging platform. Patients were excluded from comparative analysis if the data were incomplete in the dataset or they had a documented history of prior open or endovascular abdominal aortic aneurysm repair. ResultsDuring the 7-year study period, 191 FEVARs had been performed. The Cydar EV imaging platform was implemented in 2018 and used in 124 complex endovascular aneurysm repairs, including 69 consecutive FEVARs. A complete dataset was available for 137 FEVARs. With exclusion to select for de novo FEVAR, a comparative analysis was performed of 53 FEVAR without and 63 with Cydar EV imaging guidance. The cohorts were similar in patient demographics, medical comorbidities, and aortic aneurysm characteristics. No significant difference was noted between the two groups for major adverse postoperative events, length of stay, or length of intensive care unit stay. The use of Cydar EV resulted in nonsignificant decreases in the mean fluoroscopy time (69.3 ± 28 minutes vs 66.2 ± 33 minutes; P = .598) and operative time (204.4 ± 64 minutes vs 186 ± 105 minutes; P = .278). A statistically significant decrease was found in the iodinated contrast volume (105 ± 44 mL vs 83 ± 32 mL; P = .005), patient radiation exposure using the dose area product (1,049,841 mGy/cm2 vs 630,990 mGy/cm2; P < .001) and cumulative air kerma levels (4518 mGy vs 3084 mGy; P = .02) for patients undergoing FEVAR with Cydar EV guidance. ConclusionsAt our aortic center, we have observed a trend toward shorter operative times and significant reductions in both iodinated contrast use and radiation exposure during FEVAR using the Cydar EV intelligent maps. Intelligent map guidance improved the efficiency of complex endovascular aneurysm repair, providing a safer intervention for both patient and practitioner.

Surgical Effects of Resecting Skull Base Tumors Using Pre-operative Multimodal Image Fusion Technology: A Retrospective Study.

ObjectivesTo analyze the surgical effects of resecting skull base tumors using multimodal three-dimensional (3D) image fusion technology in the neurosurgery department and present some typical cases.MethodsFrom October 2019 to October 2021, we included 47 consecutive patients with skull base tumors in the Neurosurgery Department at Zhuhai People's Hospital in this study. Pre-operative head computed tomography and magnetic resonance imaging data acquisition was performed using the GE AW workstation software for registration fusion, image fusion, and 3D reconstruction. The surgical approach and surgical plan were designed based on the multimodal 3D image, and the resection rate, complication rate, and operative time of the surgery using the multimodal image fusion technique were analyzed.ResultsThe reconstructed multimodal 3D images precisely demonstrated the size, location, and shape of the tumor along with the anatomical relationship between the tumor and surrounding structures, which is consistent with the intraoperative findings. Among 47 patients, 39 patients (78.7%) underwent total resection, 5 (14.9%) underwent subtotal resection, and 3 (6.4%) underwent partial resection. The mean operative time was 4.42 ± 1.32 h. No patient died during the inpatient period. Post-operative complications included 6 cases of cerebrospinal fluid leakage (14.9%), 3 cases of intracranial infection (6.4%), 6 cases of facial paralysis (12.8%), 2 cases of dysphagia (4.3%), and 1 case of diplopia (2.1%), all of which were improved after symptomatic treatment. The application value of pre-operative 3D image fusion technology was evaluated as outstanding in 40 cases (85.1%) and valuable in 7 cases (14.9%).ConclusionsPre-operative multimodal image fusion technology can provide valuable visual information in skull base tumor surgery and help neurosurgeons design the surgical incision, choose a more rational surgical approach, and precisely resect the tumor. The multimodal image fusion technique should be strongly recommended for skull base tumor surgery.

Cloud-based Fusion Imaging Improves Operative Metrics During Fenestrated Endovascular Aneurysm Repair

Endovascular treatment of complex aortic pathology is associated with increases in procedural-related metrics including operative time and radiation exposure. Three-dimensional fusion imaging technology has decreased radiation dose and iodinated contrast use in endovascular aneurysm repair. The aim of this study is to report our institutional experience with use of a cloud-based fusion imaging platform in fenestrated endovascular aneurysm repair (FEVAR). A retrospective review of a prospectively maintained aortic database was performed to identify all patients who underwent commercially-available FEVAR (Zenith Fenestrated, Cook Medical, Bloomington, Ind) between 2013 and 2020, as well as all endovascular aneurysm repairs performed using Cydar EV Intelligent Maps (Cydar Medical, Cambridge, UK). The Cydar EV cohort was reviewed further to select all FEVAR performed with intelligent map guidance. Patient demographics, clinical, and procedural-related metrics were analyzed, with comparative analysis of FEVAR performed without and with the Cydar EV imaging platform. Patients were excluded from the comparative analysis if incomplete in the data set, or if documented history of prior open or endovascular abdominal aortic aneurysm repair. Over the 7-year study period 191 FEVAR were performed. The Cydar EV imaging platform was implemented in 2018 and used in 124 complex endovascular aneurysm repairs, including 69 consecutive FEVAR. A complete dataset was available on 137 FEVAR. With exclusions to select for de novo FEVAR, comparative analysis was performed on 53 FEVAR without and 63 with Cydar EV. Cohorts were similar with respect to patient demographics, medical comorbidities, and aortic aneurysm characteristics. No significant difference was noted between groups on major adverse postoperative events, length of stay, or length of intensive care unit stay. Use of the Cydar EV resulted in nonsignificant decreases in mean fluoroscopy time (69.3 minutes vs 66.2 minutes; P = .598), and a positive trend toward shorter operative times (204.4 minutes vs 186 minutes; P = .278). Notably, a statistically significant decrease in both iodinated contrast volume (104.7 mL vs 83.8 mL; P = .005), and patient radiation exposure via dose-area product (1,049,841 mGy/cm2 vs 630,990; P < .001) was observed in patients undergoing FEVAR with Cydar EV Intelligent Maps. Our aortic center has observed a trend toward shorter operative times, and significant decreased in both iodinated contrast use and radiation exposure during FEVAR with the use of Cydar EV Intelligent Maps. Intelligent map guidance improves the efficiency of complex endovascular aneurysm repair, providing a safer intervention for both patient and practitioner.

Lateral Supracerebellar Infratentorial Approach for Superior Oblique Myokymia: A Case Series.

Few reports have shown that superior oblique myokymia (SOM) may result from vascular compression of the trochlear nerve and may be curable using microvascular decompression (MVD). To report the clinical characteristics and surgical treatment of 2 cases of SOM and provide a review of the related literature. Two patients with SOM were treated using MVD with the lateral supracerebellar infratentorial approach. The patients underwent diagnostic magnetic resonance imaging and three-dimensional fusion imaging preoperatively. A lateral suboccipital craniotomy was performed in the park-bench position. The trochlear nerve and branches of the superior cerebellar artery were confirmed after opening the cerebellomesencephalic fissure over the tentorial surface of the cerebellum. The vessel, which compressed the root exit zone of the trochlear nerve, was transposed far from the nerve and attached to the surface of the midbrain using Teflon felt and fibrin glue. The first case showed compression on both the ventral and rostral sides of the trochlear nerve root exit zone, and the second showed compression only on the ventral side. Large bridging veins on the tentorial surface of the cerebellum complicated the approach in the second case. Postoperatively, both patients had immediate and complete resolution of symptoms without recurrence at the 24-mo and 17-mo follow-ups, respectively. Five previous reports described the complete resolution of SOM after MVD. A presentation of an intermittent fluttering ocular sensation should prompt magnetic resonance imaging for ipsilateral trochlear nerve compression. The lateral supracerebellar infratentorial approach allows safe and efficacious MVD for SOM.

Virtual surgical analysis of endoscopic microvascular decompression for hemifacial spasm

ObjectiveEndoscopic microvascular decompression (eMVD) for hemifacial spasm (HFS) clearly demonstrates the root entry zone (REZ) of the facial nerve with minimal invasiveness. The aim of this study was to identify the trajectory of the angled view under eMVD for HFS and to better understand the relevant anatomical landmarks using a virtual straight microscopic view on three-dimensional (3D) fusion images. MethodsEach 3D fusion image including arteries, veins, brainstem, cranial nerves, and skull was created using an image processing workstation. A trajectory of view under a 30° angled endoscope was defined as the angled view trajectory (AVT). To investigate the anatomy along the AVT, 3D fusion images were manually made consistent with the 30° endoscopic view, and a straight microscopic approach to obtain the same view as the endoscopic surgery was analyzed on 3D fusion images. ResultsThe 30° endoscopic view during eMVD visualized the lateral side of the pons, pontomedullary junction, REZ of the facial nerve, and offending arteries. The 30° endoscopic view correlated with 3D fusion images from the straight microscopic view obtained by the posterior petrosal approach after mastoidectomy with incision of the transition between the sigmoid sinus and jugular bulb. ConclusionsThis 3D fusion image analysis revealed the AVT of eMVD for HFS. The present results explain how the angled endoscope can effectively visualize the REZ of the facial nerve without needing extensive skull base resection.

Evaluation of the Application Effect of Contrast-Enhanced Ultrasound Image Technology Based on Three-Dimensional Image Fusion Algorithm in the Diagnosis of Adenomyosis

In this paper, the effect of ultrasound images based on a 3-dimensional image fusion algorithm in the diagnosis of adenomyosis was evaluated. 88 patients with adenomyosis who were treated in the hospital from February 2019 to May 2020 were selected as the research subjects. They were rolled into localized type (Group A), with 40 cases, and diffuse type (Group B), with 48 cases. At the same time, 45 women of normal childbearing age who underwent physical examination in the outpatient clinic were rolled into the control group (Group C). Three-dimensional ultrasound scans of the uterus were performed on all patients, to observe the enhancement methods and characteristics. Then, the image characteristics of adenomyosis were studied through the time-intensity curve (TIC). Arise time ATs of three groups of patients were not different greatly ( P &gt; 0.05 ). It was found that the enhancement method, enhancement uniformity, and enhancement level of ultrasound scan in Groups A and B were significantly different from Group C ( P &lt; 0.05 ). In contrast with Group C, the rise time (RT) of the ultrasound scan of the two groups was less, the time-to-peak (TTP) was faster, and the image maximum (IMAX) was higher ( P &lt; 0.05 ). What is more, contrast-enhanced ultrasonic (CEUS) detection in patients with adenomyosis showed centrality and nonuniform high enhancement. Besides, less RT, faster TTP, and higher IMAX than the normal population can be the key evidence for the clinical diagnosis of adenomyosis. In conclusion, according to the blood supply characteristics of adenomyosis and other gynecological diseases, the enhancement method and enhancement time of ultrasound images are significantly different. TIC can reflect the hemodynamic difference between the lesion and the normal ones. Therefore, the CEUS based on the three-dimensional image fusion algorithm can be applied to the image diagnosis of adenomyosis.

Application of High-Resolution Flat Detector Computed Tomography in Stent Implantation for Intracranial Atherosclerotic Stenosis.

ObjectiveTo evaluate the utility of high-resolution flat-detector computed tomography (HR-FDCT) compared with conventional flat-detector computed tomography (FDCT) for stent placement in symptomatic intracranial atherosclerotic stenosis (ICAS).MethodsWe retrospectively reviewed the clinical data of 116 patients with symptomatic ICAS who underwent stent implantation. Images were acquired using conventional FDCT [voxel size = 0.43 mm (isotropic)] and HR-FDCT [voxel size = 0.15 mm (isotropic)]. Immediately after stent deployment, dual-volume three-dimensional (3D) fusion images were obtained from 3D digital subtraction angiography (DSA) and HR-FDCT. The image quality for stent visualization was graded from 0 to 2 (0: not able to assess; 1: limited, but able to assess; 2: clear visualization), and the stent-expansion status (“full,” “under-expanded” or “poor apposition”) was recorded.ResultsA total of 116 patients with symptomatic ICAS were treated successfully using 116 stents (58 NeuroformTM EZ, 42 EnterpriseTM, and 16 ApolloTM). The mean pre-stent stenosis was 80.5 ± 6.4%, which improved to 20.8 ± 6.9% after stenting. Compared with FDCT, HR-FDCT improved visualization of the fine structures of the stent to improve the image quality that significantly (mean score: 1.63 ± 0.60 vs. 0.41 ± 0.59, P < 0.001). In 19 patients, stent under-expansion (n = 11) or poor apposition (n = 8) was identified by HR-FDCT but not by conventional FDCT. After balloon dilatation, stent malapposition was shown to have improved on HR-FDCT. None of the 19 patients with stent malapposition experienced short-term complications during hospitalization or had in-stent stenosis at 6-month follow-up.ConclusionHigh-resolution flat-detector computed tomography (HR-FDCT) improves visualization of the fine structures of intracranial stents deployed for symptomatic ICAS compared with that visualized using conventional FDCT. High-resolution flat-detector computed tomography improves assessment of stent deployment and could reduce the risk of complications.

A Thrombin-Responsive Nanoprobe for In Vivo Visualization of Thrombus Formation through Three-Dimensional Optical/Computed Tomography Hybrid Imaging.

Early spontaneous detection of thrombin activation benefits precise theranostics for thrombotic vascular disease. Herein, a thrombin-responsive nanoprobe conjugated by a FITC dye, PEGylated Fe3O4 nanoparticles, and a thrombin-sensitive peptide (LASG) was constructed to visualize thrombin activation and subsequent thrombosis in vivo. The FITC dye was linked to the LASG coated on the Fe3O4 nanoparticles for sensing the thrombin activity via the Förster resonance energy transfer effect. In vitro fluorescence imaging showed that the fluorescence signal intensity increased significantly after incubation with thrombin in contrast to that of the control group (p < 0.05), and the signal intensity was enhanced with the increase in thrombin concentration. Further in vivo fluorescence imaging also revealed that the signal elevated markedly in the left common carotid artery (LCCA) lesion of the mice thrombosis model after nanoprobe injection, in contrast to that of the control + nanoprobe group (p < 0.05). Moreover, the thrombin inhibitor bivalirudin could decrease the filling defect of the LCCA. Three-dimensional fusion images of micro-CT and fluorescence confirmed that filling defects in the LCCA were nicely colocalized with fluorescence signal caused by nanoprobes. The nanoplatform based on a thrombin-activatable visualization system could provide smart responsive and dynamic imaging of thrombosis in vivo.

A novel three-dimensional MRI-CT image fusion technique for precise preoperative evaluation and treatment of capitellar osteochondritis dissecans.

We developed a novel method to create three-dimensional magnetic resonance imaging-CT (3D MRI-CT) fusion images for detailed lesion evaluation and surgical simulation in capitellar osteochondritis dissecans (COCD). This study aimed to clarify its usefulness. We enrolled 12 boys with COCD (mean age, 13.8 years) and preoperatively constructed 3D models of the humerus and articular cartilage from MR images obtained with a 3-T imager. For better visualization of the articular cartilage outline, we applied 7 kg of axial traction to the elbow during MRI. We also constructed a 3D model of the humerus from CT images. 3D MRI-CT fusion images were created using both models. The average distance difference between two corresponding points as per the 3D CT and 3D MRI models of the humerus was evaluated. Using the 3D MRI-CT fusion images, we measured longitudinal and transverse lesion diameters; evaluated articular cartilage fissures and defects, articular surface deformities, and the International Cartilage Repair Society (ICRS) classification; and validated the results using intraoperative findings. The mean average distance difference was 0.75 mm. The 3D MRI-CT fusion images accurately reproduced lesion conditions in every case and correctly predicted the ICRS classification with 100% accuracy. Preoperatively measured longitudinal and transverse lesion diameters were not significantly different from intraoperative measurements (p = 0.79, 0.32 respectively). 3D MRI-CT fusion images provide a detailed evaluation of COCD lesion severity by presenting the exact positional relationship between the articular cartilage and subchondral bone. • We developed a novel method to create three-dimensional magnetic resonance imaging-computed tomography (3D MRI-CT) fusion images for the evaluation of capitellar osteochondritis dissecans. • 3D MRI-CT fusion images enabled the accurate prediction of lesions and provided a detailed evaluation of lesion severity by presenting the exact positional relationship between the articular cartilage and subchondral bone.

Flow Diverter Apposition in Patients with Large or Giant Intracranial Aneurysms Evaluated on Three-Dimensional Fusion Images Acquired by High-Resolution Cone-Beam Computed Tomography and Digital Subtraction Angiography

To investigate flow diverter (FD) apposition on fused images acquired by high-resolution cone-beam computed tomography (CBCT) and 3-dimensional (3D) digital subtraction angiography. Patients with large or giant internal carotid artery aneurysms treated with Pipeline FDs who underwent CBCT imaging at our institution between October 2016 and May 2019 were included. Two neurosurgeons measured the maximum malapposition between FDs and vessel walls on 3D fusion images of high-resolution CBCT images displaying the FD and 3D digital subtraction angiography images displaying the vessels. Associations between the relative malapposition, FD diameter, vessel diameter, proximal and distal vessel diameter discrepancy, and siphon angle were evaluated by linear regression analysis. Inter-rater and intermethod (3D and 2D image) agreements of the malapposition measurements were assessed by Bland-Altman analysis and by interclass correlation coefficients. Images of 2 patients were excluded because of image artifacts or fusion errors, and 3D fusion images were acquired in the remaining 26 patients. Our results did not suggest that relative malapposition was associated with vessel diameter (P= 0.12), vessel diameter discrepancy (P= 0.60), or syphon angle (P= 0.34), but relative malapposition increased by an estimated 13% (95% confidence interval: 4%-23%, P= 0.006) for each 1 mm increase in FD diameter. Inter-rater and intermethod agreements for apposition measurements were excellent and good, respectively. Three-dimensional fusion images provided clear visualization of structures of both the stent and parent artery with excellent diagnostic reliability. Careful deployment may be needed for FDs with larger diameters, as they tended to have larger relative malapposition.

Surgical Simulation with Three-Dimensional Fusion Images in Patients with Arteriovenous Malformation.

In arteriovenous malformation (AVM) surgery, vessel structures should be well evaluated with angiography. However, with conventional angiography, it is sometimes difficult to distinguish each feeder and its feeding territory in the nidus. In this study, we used two software systems to create three-dimensional (3D) fusion images using multiple imaging modalities and evaluated their clinical use. In the AVM patient, data were obtained from 3D rotational angiography, rotational venography, computed tomography (CT), and magnetic resonance imaging (MRI) and superimposed into 3D fusion images using imaging software (iPLAN and Avizo). Virtual surgical fields that were quite similar to the real ones were also created with these software programs. Compared with fusion images by iPLAN, those by Avizo have higher resolution and can demarcate not only each feeder but also its supplying territory in the nidus with different colors.In conclusion, 3D fusion images in AVM surgery are helpful for simulation, even though it takes time and requires special skill to create them.

A new scoring system for predicting extent of resection in medial sphenoid wing meningiomas based on three-dimensional multimodality fusion imaging

BackgroundThree-dimensional (3D) fusion imaging has been proved to be a promising neurosurgical tool for presurgical evaluation of tumor removal. We aim to develop a scoring system based on this new tool to predict the resection grade of medial sphenoid wing meningiomas (mSWM) intuitively.MethodsWe included 46 patients treated for mSWM from 2014 to 2019 to evaluate their tumors’ location, volume, cavernous sinus involvement, vascular encasement, and bone invasion by 3D multimodality fusion imaging. A scoring system based on the significant parameters detected by statistical analysis was created and evaluated.ResultsThe tumor volumes ranged from 0.8 cm3 to 171.9 cm3. A total of 39 (84.8%) patients had arterial involvement. Cavernous sinus (CS) involvement was observed in 23 patients (50.0%) and bone invasion was noted in 10 patients (21.7%). Simpson I resection was achieved in 10 patients (21.7%) and Simpson II resection was achieved in 17 patients (37.0%). Fifteen patients (32.6%) underwent Simpson III resection and 4 patients (8.7%) underwent Simpson IV resections. A scoring system was created. The score ranged from 1 to 10 and the mean score of our patients was 5.3 ± 2.8. Strong positive monotonic correlation existed between the score and resection grade (Rs = 0.772, P < 0.001). The scoring system had good predictive capacity with an accuracy of 69.60%.ConclusionsWe described a scoring system that enabled neurosurgeons to predict extent of resection and outcomes for mSWM preoperatively with 3D multimodality fusion imaging.Trial registrationRetrospectively registered