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Background In recent years, the development of digital imaging technology has had a significant influence in liver surgery. The ability to obtain a 3-dimensional (3D) visualization of the liver anatomy has provided surgery with virtual reality of simulation 3D computer models, 3D printing models and more recently holograms and augmented reality (when virtual reality knowledge is superimposed onto reality). In addition, the utilization of real-time fluorescent imaging techniques based on indocyanine green (ICG) uptake allows clinicians to precisely delineate the liver anatomy and/or tumors within the parenchyma, applying the knowledge obtained preoperatively through digital imaging. The combination of both has transformed the abstract thinking until now based on 2D imaging into a 3D preoperative conception (virtual reality), enhanced with real-time visualization of the fluorescent liver structures, effectively facilitating intraoperative navigated liver surgery (augmented reality). Data sources A literature search was performed from inception until January 2021 in MEDLINE (PubMed), Embase, Cochrane library and database for systematic reviews (CDSR), Google Scholar, and National Institute for Health and Clinical Excellence (NICE) databases. Results Fifty-one pertinent articles were retrieved and included. The different types of digital imaging technologies and the real-time navigated liver surgery were estimated and compared. Conclusions ICG fluorescent imaging techniques can contribute essentially to the real-time definition of liver segments; as a result, precise hepatic resection can be guided by the presence of fluorescence. Furthermore, 3D models can help essentially to further advancing of precision in hepatic surgery by permitting estimation of liver volume and functional liver remnant, delineation of resection lines along the liver segments and evaluation of tumor margins. In liver transplantation and especially in living donor liver transplantation (LDLT), 3D printed models of the donor's liver and models of the recipient's hilar anatomy can contribute further to improving the results. In particular, pediatric LDLT abdominal cavity models can help to manage the largest challenge of this procedure, namely large-for-size syndrome.

Meningioma consistency is one of the most critical factors affecting the difficulty of surgery. Although many studies have attempted to predict meningioma consistency via magnetic resonance imaging findings, no definitive method has been established, because most have been based on qualitative evaluations. Therefore, the present study examined the potential of the T2 relaxation time (T2 value), a tissue-specific quantitative parameter, for assessment of meningioma consistency.Eighteen surgically treated meningiomas in 16 patients were included in the present study. Preoperatively, the T2 values of all meningiomas were calculated pixel by pixel, and a T2 value distribution map was generated. A total of 27 tumor specimens (multiple specimens were procured if heterogeneous) were taken from these meningiomas, with each localization identified intraoperatively using image guidance. The consistency of the specimens was measured with a durometer, originally a device for measuring the hardness of material such as elastic rubber, and their water content was subsequently measured using wet and dry measurements.A significant correlation was found between the T2 values of the matched locations identified by image guidance intraoperatively and the consistency measured using the durometer (r = -0.722; P0.01) and the water content (r = 0.621; P = 0.01). In addition, the water content correlated significantly with the durometer consistency (r = -0.677; P0.01).The T2 values could be a reliable quantitative predictor of meningioma consistency, and the T2 value distribution map, which elucidated the internal structure of the tumor in detail, could provide helpful information for surgical resection.

OBJECTIVE Cortical bone trajectory (CBT) screw insertion using a freehand technique is considered less feasible than guided techniques, due to the lack of readily identifiable visual landmarks. However, in posterior lumbar interbody fusion (PLIF), after resection of the posterior anatomy, the pedicles themselves, into which implantation is performed, are palpable from the spinal canal and neural foramen. With the help of pedicle wall probing, the authors have placed CBT screws using a freehand technique without image guidance in PLIF. This technique has advantages of no radiation exposure and no requirement for expensive devices, but the disadvantage of reduced accuracy in screw placement. To address the problem of symptomatic breaches with this freehand technique, variables related to unacceptable screw positioning and need for revisions were investigated. METHODS From 2014 to 2020, 182 of 426 patients with single-level PLIF were enrolled according to the combined criteria of L4–5 level, excluding cases of revision and isthmic spondylolisthesis; using screws 5.5 mm in diameter; and operated by right-handed surgeons. We studied the number of misplaced screws found and replaced during initial surgeries. Using multiplanar reconstruction CT postoperatively, 692 screw positions on images were classified using previously reported grading criteria. Details of pedicle breaches requiring revisions were studied. We conducted a statistical analysis of the relationship between unacceptable (perforations > 2 mm) misplacements and four variables: level, laterality, spinal deformity, and experiences of surgeons. RESULTS Three screws in L4 and another in L5 were revised during initial surgeries. The total rate of unacceptable screws on CT examinations was 3.3%. Three screws in L4 and another in L5 breached inferomedial pedicle walls in grade 3 and required revisions. The revision rate was 2.2%. The percentage of unacceptable screws was 5.2% in L4 and 1.7% in L5 (p < 0.05), whereas other variables showed no significant differences. CONCLUSIONS A freehand technique can be feasible for CBT screw insertion in PLIF, balancing the risks of 3.3% unacceptable misplacements and 2.2% revisions with the benefits of no radiation exposure and no need for expensive devices. Pedicle palpation in L4 is the key to safety, even though it requires deeper and more difficult probing. In the initial surgeries and revisions, 75% of revised screws were observed in L4, and unacceptable screw positions were more likely to be found in L4 than in L5.

Focused ultrasound (FUS) lacks reliable real-time image guidance, which hinders the development of non-invasive ultrasound treatment in many important clinical applications. A dual-mode ultrasound array, capable of both imaging and therapy offers a new and reliable strategy for image-guided ultrasound therapy applications. The strategy has the advantages of real-time use, low cost, portability and inherent registration between imaging and therapeutic coordinate systems. In this work, a dual-mode two-dimensional (2D) matrix array with 1 MHz center frequency and 256 elements for ultrasound image-guided non-invasive therapy is reported. The array can provide three-dimensional (3D) volumetric ultrasound imaging and 3D focus control. Ultrasound imaging and therapeutic applications for the brain of small animals demonstrated the multi-functional capability of the dual-mode 2D matrix array. A method of rat brain positioning based on ultrasound imaging was proposed and verified. Transcranial ultrasound image-guided blood–brain barrier (BBB) opening of multiple-targets was achieved in vivo, using the proposed dual-mode 2D array. The obtained results indicate that the dual-mode 2D matrix array is a promising method for practical use in ultrasound image-guided non-invasive therapy applications.

PURPOSE/OBJECTIVES: To estimate the effects of interfractional anatomic changes on dose to organs-at-risk (OARs) and tumors, as measured with cone-beam computed tomography (CBCT) image guidance for pancreatic stereotactic body radiotherapy (SBRT). MATERIALS/METHODS: We evaluated 11 patients with pancreatic cancer, whom were treated with SBRT (33–40 Gy in 5 fractions) using daily CT-on-rails (CTOR) image guidance immediately before treatment with breath-hold motion management. CBCT alignment was simulated in the treatment planning software by aligning the original planning CT to each fractional CTOR image set via fiducial markers. CTOR datasets were used to calculate fractional doses after alignment by applying the rigid shift of the planning CT and CTOR image sets to the planning treatment isocenter and recalculating the fractional dose. Accumulated dose to the gross tumor volume (GTV), tumor vessel interface (TVI), duodenum, small bowel, and stomach were calculated by summing the 5 fractional absolute dose-volume histograms (DVHs) into a single DVH for comparison with the original planned dose. RESULTS: Four patients had a GTV D100% of at least 1.5 Gy less than the fractional planned value in several fractions; 4 patients had fractional underestimation of duodenum dose by 1.0 Gy per fraction. The D1.0 cm(3)

With recent advances in imaging technology, the frequency of detecting musculoskeletal lesions has also increased. Percutaneous image-guided needle biopsy is occasionally required for the diagnosis of such lesions. Moreover, in the era of personalized cancer care, chances in histopathological diagnosis and the importance of histopathological diagnosis by percutaneous needle biopsy are increasing. However, as percutaneous needle biopsy is not a common procedure for musculoskeletal lesions, careful planning and the application of adequate techniques such as hydrodissection and the trans-osseous approach are occasionally required. In this review, we have summarized the indications and techniques for percutaneous image-guided needle biopsy for musculoskeletal lesions, including lymphatic lesions.

Introduction: Screening for coronavirus disease 2019 (COVID-19) exposure, coupled with engaged decision making to prioritize cancer treatment in parallel with reducing risk of exposure and infection, is crucial in the management of COVID-19 during cancer treatment. After two reported case studies of imaging findings during daily computed tomography (CT)-based image-guided radio-therapy (RT) scans, a call for submission of anonymized case reports was published with the objective of rapidly determining if there was a correlation between the onset of new pulmonary infiltrates found during RT and COVID-19. We hereby report the results of the aggregate analysis. Methods: Data of deidentified case reports for patients who developed biochemically confirmed COVID-19 during RT were submitted through an online portal. Information requested included a patient's sex, age, cancer diagnosis and treatment, and COVID-19 diagnosis and outcome. Coplanar CT-based imaging was requested to reveal the presence or absence of ground-glass opacities or infiltrates. Results: A total of seven reports were submitted from Turkey, Spain, Belgium, Egypt, and the United States. Results and imaging from the patients reported by Suppli et al. and McGinnis et al. were included for a total of nine patients for analysis. All patients were confirmed COVID-19 positive using polymerase chain reaction-based methods or nasopharyngeal swabs. Of the nine patients analyzed, abnormalities consistent with ground-glass opacities or in- filtrates were observed in eight patients. Conclusions: This is the largest case series revealing the potential use of CT-based image guidance during RT as a tool for identifying patients who need further workup for COVID-19. Considerations for reviewing image guidance for new pulmonary infiltrates and immediate COVID-19 testing in patients who develop new infiltrates even without COVID-19 symptoms are strongly encouraged. (c) 2021 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

Objective Surgery is the standard treatment for most tumors in the prestyloid parapharyngeal space (PPS) but it can be a challenging procedure because of the anatomical complexity of the area. Prestyloid surgery can be performed with various lateral approaches or with a medial approach using transoral robotic surgery (TORS)—either alone or in combination with a transcervical incision. We have retrospectively compared our center's results with lateral and medial approaches. Methods Between 2015 and 2020, 28 patients with prestyloid PPS tumors underwent surgery at our center: 14 with lateral approaches, including transcervical, transcervical‐parotid, and transcervical‐mandibular, and 14 with medial approaches (12 with TORS and two with TORS plus a transcervical incision). We compared surgical time, postsurgical complications, length of hospital stay, need for feeding tube, and relapse‐free survival in the two patient groups. Results Pleomorphic adenoma was the most frequent tumor and 60.7% of the tumors were benign. Tumor volume and maximum length were similar in the two groups of patients. Intraoperative image guidance and ultrasound were used in 33% of TORS. TORS was associated with less surgical time, fewer complications, and shorter hospital stays. Recurrence rates were similar in the two groups. Conclusion The medial approach by TORS offers superior results in prestyloid tumors than the open lateral approach and can be refined by intraoperative guidance. Level of Evidence: 4, Retrospective analysis of prestyloid parapharyngeal tumors patients comparing lateral surgical approach vs medial (TORS). Internal carotid artery position and parotid gland involvement are crucial points to consider in choosing a medial or lateral approach in prestyloid tumors. We can recommend the use of TORS approach in selected cases on experienced hands.

Purpose Scientific and clinical achievements in radiation, medical, and surgical oncology are changing the landscape of interdisciplinary oncology. The German Society for Radiation Oncology (DEGRO) working group of young clinicians and scientists (yDEGRO) and the DEGRO representation of associate and full professors (AKRO) are aware of the essential role of radiation oncology in multidisciplinary treatment approaches. Together, yDEGRO and AKRO endorsed developing a German radiotherapy & radiation oncology vision 2030 to address future challenges in patient care, research, and education. The vision 2030 aims to identify priorities and goals for the next decade in the field of radiation oncology. Methods The vision development comprised three phases. During the first phase, areas of interest, objectives, and the process of vision development were defined jointly by the yDEGRO, AKRO, and the DEGRO board. In the second phase, a one-day strategy retreat was held to develop AKRO and yDEGRO representatives’ final vision from medicine, biology, and physics. The third phase was dedicated to vision interpretation and program development by yDEGRO representatives. Results The strategy retreat’s development process resulted in conception of the final vision “Innovative radiation oncology Together – Precise, Personalized, Human.” The first term “Innovative radiation oncology” comprises the promotion of preclinical research and clinical trials and highlights the development of a national committee for strategic development in radiation oncology research. The term “together” underpins collaborations within radiation oncology departments as well as with other partners in the clinical and scientific setting. “Precise” mainly covers technological precision in radiotherapy as well as targeted oncologic therapeutics. “Personalized” emphasizes biology-directed individualization of radiation treatment. Finally, “Human” underlines the patient-centered approach and points towards the need for individual longer-term career curricula for clinicians and researchers in the field. Conclusion The vision 2030 balances the ambition of physical, technological, and biological innovation as well as a comprehensive, patient-centered, and collaborative approach towards radiotherapy & radiation oncology in Germany.

Purpose: To illustrate dynamic, time-resolved CTA (d-CTA) imaging technique in characterizing aortic endoleak type/inflow using quantitative parameters and its value in providing image guidance for targeted treatment approach. Technique: Dedicated endoleak protocol involved acquiring multiple time-resolved contrast enhanced scans using third-generation CT scanner (Somatom Force®, Siemens Healthineers). Parameters such as scan field of view (FOV), kV, number/timing of scans were customized based on patient’s body-mass-index, timing bolus, and prior imaging findings. D-CTA image datasets were evaluated qualitatively and quantitatively using time-attenuation curves (TAC) analysis after motion correction using a dedicated software ( syngo.via®, Siemens). D-CTA findings from 4 illustrative cases demonstrating type I, type II (inferior mesenteric and lumbar artery inflow), and type III endoleak were illustrated. TAC analysis with time to peak parameter enabled better characterization of endoleak type and inflow. During endoleak intervention, target vessels from d-CTA images were electronically annotated and overlaid on fluoroscopy using 2D−3D image fusion to provide image guidance for targeted treatment. Conclusion: D-CTA imaging with TAC analysis characterizes aortic endoleak type and inflow, in addition to providing image guidance for targeted endoleak treatment. Such dynamic, time-resolved imaging techniques may provide further insights into understanding aortic endoleak that remains an Achilles heel for endovascular aortic aneurysm repair.

Background Endobronchial navigation is performed in a variety of ways, none of which are meeting all the clinicians' needs required to reach diagnostic success in every patient. We sought to characterize precurved and steerable guiding sheaths (GS) in endobronchial targeting for lung biopsy using cone beam computed tomography (CBCT) based augmented fluoroscopy (AF) image guidance. Methods Four precurved GS (EdgeTM 45, 90, 180, 180EW, Medtronic) and two steerable GS [6.5 F Destino Twist (DT), Oscor; 6 F Morph, BioCardia] were evaluated alone and in combination with an electromagnetic tracking (EM) guide and biopsy needles in three experimental phases: (I) bench model to assess GS deflection and perform biopsy simulations; (II) ex vivo swine lung comparing 2 steerable and 2 precurved GS; and (III) in vivo male swine lung to deliver a needle (n=2 swine) or to deliver a fiducial marker (n=2 swine) using 2 steerable GS. Ex vivo and in vivo image guidance was performed with either commercial or prototype AF image guidance software (Philips) based on either prior CT or procedural CBCT. Primary outcomes were GS delivery angle (θGS) and needle delivery angle (θN) in bench evaluation and needle delivery error (mm) (mean ± se) for ex vivo and in vivo studies. Results The steerable DT had the largest range of GS delivery angles (θN: 0-114°) with either the 21 G or 19 G biopsy needle in the bench model. In ex vivo swine lung, needle delivery errors were 8.7±0.9 mm (precurved Edge 90), 5.4±1.9 mm (precurved Edge 180), 4.7±1.2 mm (steerable DT), and 5.6±2.4 mm (steerable Morph). In vivo, the needle delivery errors for the steerable GS were 6.0±1.0 mm (DT) and 15±7.0 mm (Morph). In vivo marker coil delivery was successful for both the steerable DT and morph GS. A case report demonstrated successful needle biopsy with the steerable DT. Conclusions Endobronchial needle delivery with AF guidance is feasible without a bronchoscope with steerable GS providing comparable or improved accuracy compared to precurved GS.

This paper describes the case of a patient who developed refractory heart failure due to a fistula from the left ventricle to the coronary sinus that was unintentionally created after a surgical myectomy and mitral valve replacement. Advanced image guidance with a pre-procedure 3-dimensional physical model and intraprocedure echocardiography fusion facilitated transcatheter plugging of the shunt with symptom resolution. (Level of Difficulty: Advanced.), Central Illustration

Objective: Spinal fusion surgeries require accurate placement of pedicle screws in anatomic corridors without breaching bone boundaries. We are developing a combined ultrasound and photoacoustic image guidance system to avoid pedicle screw misplacement and accidental bone breaches, which can lead to nerve damage. Methods: Pedicle cannulation was performed on a human cadaver, with co-registered photoacoustic and ultrasound images acquired at various time points during the procedure. Bony landmarks obtained from coherence-based ultrasound images of lumbar vertebrae were registered to post-operative CT images. Registration methods were additionally tested on an ex vivo caprine vertebra. Results: Locally weighted short-lag spatial coherence (LW-SLSC) ultrasound imaging enhanced the visualization of bony structures with generalized contrast-to-noise ratios (gCNRs) of 0.99 and 0.98−1.00 in the caprine and human vertebrae, respectively. Short-lag spatial coherence (SLSC) and amplitude-based delay-and-sum (DAS) ultrasound imaging generally produced lower gCNRs of 0.98 and 0.84, respectively, in the caprine vertebra and 0.84−0.93 and 0.34−0.99, respectively, in the human vertebrae. The mean $\pm$ standard deviation of the area of −6 dB contours created from DAS photoacoustic images acquired with an optical fiber inserted in prepared pedicle holes (i.e., fiber surrounded by cancellous bone) and holes created after intentional breaches (i.e., fiber exposed to cortical bone) was 10.06 $\pm$ 5.22 mm $^2$ and 2.47 $\pm$ 0.96 mm $^2$ , respectively (p $ 0.01). Conclusions: Coherence-based LW-SLSC and SLSC beamforming improved visualization of bony anatomical landmarks for ultrasound-to-CT registration, while amplitude-based DAS beamforming successfully distinguished photoacoustic signals within the pedicle from less desirable signals characteristic of impending bone breaches. Significance: These results are promising to improve visual registration of ultrasound and photoacoustic images with CT images, as well as to assist surgeons with identifying and avoiding impending bone breaches during pedicle cannulation in spinal fusion surgeries.

The use of kilovoltage cone‐beam computed tomography (kV‐CBCT) or megavoltage computed tomography (MVCT) for image guidance prior to lung stereotactic body radiation therapy (SBRT) is common clinical practice. We demonstrate that under equivalent respiratory conditions, image guidance using both kV‐CBCT and MVCT may result in the inadequate estimation of the range of target motion under free‐breathing (FB) conditions when standard low‐density window and levels are used. Two spherical targets within a respiratory motion phantom were imaged using both long‐exhale (LE) and sinusoidal respiratory traces. MVCT and kV‐CBCT images were acquired and evaluated for peak‐to‐peak amplitudes of 10 or 20 mm in the cranial‐caudal direction, and with 2, 4 or 5 s periods. All images were visually inspected for artifacts and conformity to the ITV for each amplitude, period, trace‐type, and target size. All LE respiratory traces required a lower threshold HU window for MVCT and kV‐CBCT compared to sinusoidal traces to obtain 100% volume conformity compared with the theoretical ITV (ITVT). Excess volume was less than 2% for all kV‐CBCT contours regardless of trace‐type, breathing period, or amplitude, while the maximum excess volume for MVCT was 48%. Adjusting window and level to maximize conformity with the ITVT is necessary to reduce registration uncertainty to less than 5 mm. To fully capture target motion with either MVCT or kV‐CBCT, substantial changes in HU levels up to −600 HU are required which may not be feasible clinically depending on the target's location and surrounding tissue contrast. This registration method, utilizing a substantially decreased window and level compared to standard low‐density settings, was retrospectively compared to the automated registration algorithm for five lung SBRT patients exposed to pre‐treatment kV‐CBCT image guidance. Differences in registrations in the super‐inferior (SI) direction greater than the commonly used ITV to PTV margin of 5 mm were encountered for several cases. In conclusion, pre‐treatment image guidance for lung SBRT targets using MVCT or kV‐CBCT is unlikely to capture the full extent of target motion as defined by the ITVT and additional caution is warranted to avoid registration errors for small targets and patients with LE respiratory traces.

Background: The conventional surgical management of breast abscesses consists of an incision taken over the point at which there is maximum fluctuation (or pain) and breaking of the abscess septa by digits. Now antibiotics and repeated abscess aspiration under USG guidance is new minimally invasive method which is on rise Objectives: To study the outcome of open technique of breast abscess management. To study the outcome of closed technique of breast abscess management. To compare the outcome of open v/s closed technique of surgical management of breast abscess. Methodology: Sample will be divided into two groups and type of treatment i.e open incision and drainage or percutaneous aspiration under guidance will be decided randomly by chit system. Expected Results: Feasibility and outcome of Percutaneous drainage is better than incision and drainage Conclusion: First line management of Breast abscess will soon be percutaneous drainage under USG guidance.

BACKGROUND: The advances in image guidance and capability of highly conformal dose deliveries made possible the use of helical tomotherapy (HT) for lung cancer treatment. To determine the effect of respiratory motion on the delivered dose in HT, film dosimetry using a dynamic phantom was performed. This was a phantom study to determine the effect of motion on the delivered dose in HT. MATERIALS AND METHODS: 4D computed tomography (4DCT) was acquired for various target motions of CIRS dynamic phantom (CIRS Inc., Norfolk, USA) with 2.5cm diameter spherical target of volume 8.2 cc moving in the COS 4 motion pattern. AveIP images and treatment plans were generated in the HT planning system. Target excursions during treatment delivery were changed in the superior-inferior, anteroposterior and lateral directions. The breathing cycle time was varied from 4 to 5 sec. and also the delivery interruptions were introduced. A film was exposed for each delivery and gamma analysis was performed. RESULTS: The gamma pass rate (GPR) with 3%, 2 mm criteria for the target motion in the S-I direction showed a significant reduction from 97.5% to 54.4% as the motion increased from 3 mm to 8 mm (p = 0.03). For the target motion in S-I = 8 mm, L-R = A-P = 3 mm, the percentage decrease in the GPR was 74% (p = 0.001) for three interruptions. CONCLUSION: The ITV based approach in HT is ideal for a shallow breathing situation when the tumor excursions were confined to 5 mm in the S-I and 3 mm in L-R and A-P directions.

Technological advancement has facilitated patient-specific radiotherapy in bladder cancer. This has been made possible by developments in image-guided radiotherapy (IGRT). Particularly transformative has been the integration of volumetric imaging into the workflow. The ability to visualise the bladder target using cone beam computed tomography and magnetic resonance imaging initially assisted with determining the magnitude of inter- and intra-fraction target change. It has led to greater confidence in ascertaining true anatomy at each fraction. The increased certainty of dose delivered to the bladder has permitted the safe reduction of planning target volume margins. IGRT has therefore improved target coverage with a reduction in integral dose to the surrounding tissue. Use of IGRT to feed back into plan and dose delivery optimisation according to the anatomy of the day has enabled adaptive radiotherapy bladder solutions. Here we undertake a review of the stepwise developments underpinning IGRT and adaptive radiotherapy strategies for external beam bladder cancer radiotherapy. We present the evidence in accordance with the framework for systematic clinical evaluation of technical innovations in radiation oncology (R-IDEAL).

As an emerging minimally invasive treatment method, percutaneous ablation is more and more widely used in the treatment of liver tumors. It has been recommended by guidelines for diagnosis and treatment of hepatocellular carcinoma (HCC) as a curative treatment alongside surgical resection and liver transplantation. In recent years, with the continuous advancement and innovation of percutaneous ablation technologies, their clinical efficacy and safety have been significantly improved, which has led to the expanded application of percutaneous ablation in the treatment of HCC—more and more patients who were previously considered unsuitable for ablation therapies are now being treated with percutaneous ablation. Obviously, percutaneous ablation can reduce the risk of treatment changes from curative strategies to palliative strategies. Based on clinical practice experience, this review enumerates the advantages and disadvantages of different ablative modalities and summarizes the existing combinations of ablation techniques, thus will help clinicians choose the most appropriate ablative modality for each patient and will provide scientific guidance for improving prognosis and making evidence-based treatment decisions. In addition, we point out the challenges and future prospects of the ablation therapies, thereby providing direction for future research.

Purpose To show the feasibility of 3D-printed fixation masks for whole brain radiation therapy in a clinical setting and perform a first comparison to an established thermoplastic mask system. Methods Six patients were irradiated with whole brain radiotherapy using individually 3D-printed masks. Daily image guidance and position correction were performed prior to each irradiation fraction. The vectors of the daily position correction were compared to two collectives of patients, who were irradiated using the standard thermoplastic mask system (one cohort with head masks; one cohort with head and neck masks). Results The mean systematic errors in the experimental cohort ranged between 0.59 and 2.10 mm which is in a comparable range to the control groups (0.18 mm–0.68 mm and 0.34 mm–2.96 mm, respectively). The 3D-printed masks seem to be an alternative to the established thermoplastic mask systems. Nevertheless, further investigation will need to be performed. Conclusion The prevailing study showed a reliable and reproducible interfractional positioning accuracy using individually 3D-printed masks for whole brain irradiation in a clinical routine. Further investigations, especially concerning smaller target volumes or other areas of the body, need to be performed before using the system on a larger basis.

Background Traditional craniotomy relies on the surgeon's experience and can be complicated owing to excessive skull bone removal, undesirable brain tissue penetration, or severe bleeding. For craniotomy, we developed a robot system based on intraoperative cone-beam computed tomography image guidance and human-robot cooperative interaction, aiming to improve the safety and accuracy of surgery and reduce the labor-intensiveness of the procedure. Methods Intraoperative cone-beam computed tomography image guidance was adopt to improve the accuracy in our experiment. Craniotomy was performed using an interactive method based on human-robot collaboration, which could achieve a natural interactive method in accordance with surgeons' operating habits. The frequency-based method of contact distinction and the method of torque estimation were used to improve the safety of the designed robot. Results An animal experiment was conducted to verify the effectiveness of the robot system. During the drilling process, the position error was 0.92 ± 0.17 mm (upper surface) and 0.97 ± 0.11 mm (lower surface), and the angle error was 3.37 ± 1.43°. During the milling process, the position error was 1.06 ± 0.13 mm (upper surface) and 1.09 ± 0.09 mm (lower surface). The results showed that the system had sufficient precision and could better complete craniotomy with human-robot collaboration. In addition, with the feedback of multisensor information, the robot system could achieve a sufficient level of safety. Conclusions The robot system can achieve accurate positioning and safe user-friendly human-robot interaction, which solves problems encountered in the drilling and milling of craniotomy, meets clinical needs, and provides a new method for robot-assisted craniotomy.

The purpose of this retrospective study was to investigate survival outcomes and irradiated tumor control (local control [LC]) and locoregional control (LRC) after stereotactic body radiotherapy (SBRT) for T1 or recurrent T1 (rT1) kidney cancer. Twenty-nine nonconsecutive patients with 30 tumors were included. SBRT doses of 70 Gy, 60 Gy or 50 Gy in 10 fractions were prescribed with a linear accelerator using daily image guidance. The Kaplan–Meier method was used to estimate time-to-event outcomes, and the log-rank test was used to compare survival curves between groups divided by each possible factor. The median follow-up periods for all patients and survivors were 57 months and 69.6 months, respectively. The five-year LC rate, LRC rate, progression-free survival (PFS) rate, disease-specific survival (DSS) rate and overall survival (OS) rate were 94%, 88%, 50%, 96% and 68%, respectively. No significant factor was related to OS and PFS. Three of 24 non-hemodialysis (HD) patients had new-onset-HD because of the progression of underlying kidney disease. Grade 3 or higher toxicities from SBRT did not occur. In conclusion, SBRT for kidney cancer provided a high rate of LC, LRC and DSS with minimal toxicities, but patient selection and indication for SBRT should be done carefully considering the relatively low OS rate.

Objective The purpose of this study is to propose a surgical plan based on augmented reality (AR) and guide template technology for restoration of nasal deformities, and evaluate its feasibility and clinical efficacy. Methods Patients were scanned with a FaceScan to obtain the three-dimensional (3D) facial model, and computed tomography was also performed to obtain the maxillofacial computed tomography images while wearing the artificial marker. The mirroring tool and database searching and matching technology were employed to restore the nasal deformities for a normal nose (preoperative planning model). The design of guide template for deciding the incision area was based on the preoperative planning model, which was also imported into the AR image guidance system named HuaxiAR1.0 for reconstruction of the nose contour. One week after the surgery, the postoperative 3D facial model was obtained. Then, the clinical efficacy was evaluated by comparing the difference between the preoperative planning and postoperative 3D facial model. Results The patients obtained satisfactory nasal shapes after surgery. Comparison of the difference between the preoperative and postoperative 3D model revealed that the maximum error was ranging from 2.24 mm to 3.10 mm with the mean error from 0.54 mm to 0.65 mm. Conclusion The combined application of AR and guide template technology provides a new approach for the treatment of nasal deformities, and has a certain significance in realizing the precise repair of other craniofacial soft tissue deformities.

Success rates of lumbar punctures (LPs) in children are reportedly as low as 50%. In addition to procedural complications and failure, difficult LPs are a risk factor for traumatic LPs (TLPs), which can potentially affect diagnostic utility and alter treatment plans for pediatric oncology patients. To identify the intrinsic factors associated with technically difficult LPs in the pediatric oncology population, we performed a retrospective review of patients who required diagnostic imaging modalities for LP procedures at a single pediatric oncology institution between September 2008 and November 2018. We evaluated data from 64 LPs performed in 33 patients who were referred for image-guided LPs after undergoing technically difficult LPs that were unsuccessful using anatomic landmarks. In these cases, 96.9% of patients had at least one of the following intrinsic factors: body mass index (BMI) ≥ 25, anatomic spinal abnormalities, history of ≥ 5 previous LPs, age < 12 months, and history of back surgery. Elevated BMI was the most common factor associated with difficult LP (81.8%), followed by spinal abnormalities (51.5%), and history of ≥ 5 previous LPs (33.3%). Age < 12 months and history of back surgery were also associated with difficult LPs, but at a lower frequency. On the basis of these findings, we propose clinical recommendations for preprocedural identification of patients at risk of difficult LPs to reduce complications, including TLP, failure, and exposure to general anesthesia.

Background Adoption of navigated total knee arthroplasty (Nav-TKA) is increasing. However, it has been suggested that a perceived decrease in surgical efficiency and a lack of proven superior functional outcomes associated with Nav-TKA have hindered its widespread adoption. Methods The American College of Surgeons National Surgical Quality Improvement Program was queried to identify patients who had undergone TKA with or without navigation between 2012 and 2018. Patients were further subclassified based on the type of navigation used, image-guided or imageless. Multivariate logistic regression was used to compare operative time and 30-day complication rates between conventional TKA (Conv-TKA) and Nav-TKA with and without image guidance. Results A total of 316,210 Conv-TKAs and 8554 Nav-TKAs (8270 imageless, 284 image-guided) were identified. Across the study period, the use of Nav-TKA was associated with a 1.5-minute increase in operative time. However, the overall time burden decreased over the study period, and by 2018, the mean operative time for Nav-TKA was 2.4 minutes less than that of Conv-TKA. Compared with Conv-TKA, Nav-TKA was associated with decreased rates of postoperative transfusion and surgical site complications but a similar incidence of systemic thromboembolism. Conclusions This is the first large-scale database study to examine the differences in operative time between Conv-TKA and Nav-TKA. The time burden associated with Nav-TKA decreased over the study period and even reversed by 2018. Nav-TKA was associated with lower rates of postoperative transfusion and surgical site complications. Further studies are needed to evaluate the long-term and functional outcomes between conventional and navigated knee arthroplasty techniques.

Background and purpose Transperineal ultrasound (TPUS) is used clinically for directly assessing prostate motion. Factors affecting accuracy and precision in TPUS motion estimation must be assessed to realise its full potential. Methods and materials Patients were imaged using volumetric TPUS during the Clarity-Pro trial (NCT02388308). Prostate motion was measured online at patient set-up and offline by experienced observers. Cone beam CT with markers was used as a comparator and observer performance was also quantified. The influence of different clinical factors was examined to establish specific recommendations towards efficacious ultrasound guided radiotherapy. Results From 330 fractions in 22 patients, offline observer random errors were 1.5 mm, 1.3 mm, 1.9 mm (left–right, superior-inferior, anteroposterior respectively). Errors increased in fractions exhibiting poor image quality to 3.3 mm, 3.3 mm and 6.8 mm. Poor image quality was associated with inconsistent probe placement, large anatomical changes and unfavourable imaging conditions within the patient. Online matching exhibited increased observer errors of: 3.2 mm, 2.9 mm and 4.7 mm. Four patients exhibited large systematic residual errors, of which three had poor quality images. Patient habitus showed no correlation with observer error, residual error, or image quality. Conclusions TPUS offers the unique potential to directly assess inter- and intra-fraction motion on conventional linacs. Inconsistent image quality, inexperienced operators and the pressures of the clinical environment may degrade precision and accuracy. Experienced operators are essential and cross-centre standards for training and QA should be established that build upon current guidance. Greater use of automation technologies may further minimise uncertainties.

BACKGROUND Percutaneous radiofrequency ablation (RFA) is an effective treatment for unresectable hepatocellular carcinoma (HCC) and a minimally invasive alternative to hepatectomy for treating tumour recurrence. RFA is often performed using contrast-enhanced computed tomography (CECT) and/or ultrasonography. In recent years, angiographic systems with flat panel image detectors and advanced image reconstruction algorithms have broadened the clinical applications of cone-beam computed tomography (CBCT), including RFA. Several studies have shown the effectiveness of using CBCT for immediate treatment assessments and follow-ups. AIM To assess the treatment response to RFA for HCC using CBCT. METHODS Forty-eight patients (44 men; aged 37-89 years) with solitary HCC [median size: 3.2 (1.2-6.6) cm] underwent RFA and were followed for 25.6 (median; 13.5-35.2) mo. Image fusion of CBCT and pre-operative CECT or magnetic resonance imaging (MRI) was used for tumour segmentation and needle path and ablation zone planning. Real-time image guidance was provided by overlaying the three-dimensional image of the tumour and needle path on the fluoroscopy image. Treatment response was categorized as complete response (CR), partial response (PR), stable disease (SD), or progressive disease (PD). Disease progression, death, time to progression (TTP), and overall survival (OS) were recorded. Kaplan-Meier and Cox regression analyses were performed. RESULTS Initial post-RFA CECT/MRI showed 38 cases of CR (79.2%), 10 of PR (20.8%), 0 of SD, and 0 of PD, which strongly correlated with the planning estimation (42 CR, 87.5%; 6 PR, 12.5%; 0 SD; and 0 PD; accuracy: 91.7%, P < 0.01). Ten (20.8%) patients died, and disease progression occurred in 31 (35.4%, median TTP: 12.8 mo) patients, resulting in 12-, 24-, and 35-mo OS rates of 100%, 81.2%, and 72.2%, respectively, and progression-free survival (PFS) rates of 54.2%, 37.1%, and 37.1%, respectively. The median dose-area product of the procedures was 79.05 Gy*cm2 (range 40.95-146.24 Gy*cm2), and the median effective dose was 10.27 mSv (range 5.32-19.01 mSv). Tumour size < 2 cm (P = 0.008) was a significant factor for OS, while age (P = 0.001), tumour size < 2 cm (P < 0.001), tumour stage (P = 0.010), and initial treatment response (P = 0.003) were significant factors for PFS. CONCLUSION Reliable RFA treatment planning and satisfactory outcomes can be achieved with CBCT.

Objective Is daily image‐guided radiation therapy justified for all patients? Here, we attempt to address this issue and present data obtained from various frequencies. Methods All consecutive head and neck cancer patients receiving radiation with curative intent and daily image‐guided radiation therapy using kV cone beam computed tomography scans were eligible. Displacements in the medial–lateral, superior–inferior (SI), and anterior–posterior directions were documented daily. The retrospectively simulated scenarios with reducing frequency were 50%, 30%, 20%, and 10%. The mean displacements, systematic errors, random errors, and planning target volume margins were calculated. Results A total of 831 cone beam computed tomography scans of 31 patients were analyzed, showing normally distributed mean displacements in the medial–lateral, SI, and anterior–posterior direction, except in SI for daily format. The mean displacements in the three directions was

Purpose We aimed to present our initial clinical experience on the implementation of a stereotactic MR-guided online adaptive radiation therapy (SMART) for the treatment of liver metastases in oligometastatic disease. Materials and methods Twenty-one patients (24 lesions) with liver metastasis treated with SMART were included in this retrospective study. Step-and-shoot intensity-modulated radiotherapy technique was used with daily plan adaptation. During delivery, real-time imaging was used by acquiring planar magnetic resonance images in sagittal plane for monitoring and gating. Acute and late toxicities were recorded both during treatment and follow-up visits. Results The median follow-up time was 11.6 months (range, 2.2 to 24.6 months). The median delivered total dose was 50 Gy (range, 40 to 60 Gy); with a median fraction number of 5 (range, 3 to 8 fractions) and the median fraction dose was 10 Gy (range, 7.5 to 18 Gy). Ninety-three fractions (83.7%) among 111 fractions were re-optimized. No patients were lost to follow-up and all patients were alive except one at the time of analysis. All of the patients had either complete (80.9%) or partial (19.1%) response at irradiated sites. Estimated 1-year overall survival was 93.3%. Intrahepatic and extrahepatic progression-free survival was 89.7% and 73.5% at 1 year, respectively. There was no grade 3 or higher acute or late toxicities experienced during the treatment and follow-up course. Conclusion SMART represents a new, noninvasive and effective alternative to current ablative radiotherapy methods for treatment of liver metastases in oligometastatic disease with the advantages of better visualization of soft tissue, real-time tumor tracking and potentially reduced toxicity to organs at risk.

Background: Insersion of subcutaneous poracath is im-portant in some cancer cases for whom chemotherapy isindicated. It is done either through image guided techniquein Intrerventional Departement or through blind technique inthe Surgical Departement.Aim of Study: We aimed in our study to to evaluate thecomplications and advantages of the two methodes used forportacath insertion (image-guided inserion and anatomicallandmark blind technique) and compare both to detect thebetter one should be used for the pateints.Patients and Methods: 110 adult cancer patients referredfrom the Medical Oncology Department outpatient clinics forsubcutaneous port catheter insertion in the period from January2019 to January 2020. 55 pateints underwent image-guidedinserion technique, while the other 55 pateints underwent theanatomical landmark blind technique. Data were collectedand analyzed. We campared the feasibility, advantages andcomplications of each technique.Results: The results showed obvious decreased complica-tions in image guided port catheter insertion compared toanatomical landmark blind technique in adult cancer patientsindicated for chemotherapy.Conclusion: Image guided portacath insertion is moresafe than anatomical landmark blind insertion.

Introduction This study assessed the impact of dosimetry to both the target and normal tissue when either bony anatomy (BA) or prostate (PRO) was used as surrogates for image guidance for pelvis and prostate radiotherapy using a dose accumulation process. Methods Thirty patients who were prescribed 50–54Gy to the pelvic lymph nodes (PLN) and 78Gy to the prostate/seminal vesicles were included. Daily acquired CBCTs were rigidly registered to the CT using BA and PRO to simulate two different treatment positions. The accumulated delivered dose (DAcc) of PLN, prostate, bladder and rectum for each surrogate were compared with the planned dose. Deviation from the planned dose (ΔDAcc-Plan) of >5% was considered clinically significant. Results Prostate was displaced from bony anatomy by > 5 mm in 96/755 fractions (12.7%). Deviation between the mean DAcc and the planned dose for PLN and prostate was 0.2). In contrary, DAcc for rectum D50 was significantly greater than the planned dose when BA was used (Mean ΔDAcc-Plan = 6%). When examining individual patient, deviation from the planned dose for rectum D50 was clinically significant for 18 patients for BA (Range: 5–21%) and only 8 patients for PRO (Range: 5–8%). Conclusions The use of either BA or PRO for image guidance could deliver dose to PLN and prostate with minimal deviation from the plan using existing PTV margins. However, deviation for rectum was greater when BA was used.

Chemically functionalized gas-filled bubbles with a versatile micro/nano-sized scale have witnessed a long history of developments and emerging applications in disease diagnosis and treatments. In combination with ultrasound and image-guidance, micro/nanobubbles have been endowed with the capabilities of biomedical imaging, drug delivery, gene transfection and disease-oriented therapy. As an external stimulus, ultrasound (US)-mediated targeting treatments have been achieving unprecedented efficiency. Nowadays, US is playing a crucial role in visualizing biological/pathological changes in lives as a reliable imaging technique and a powerful therapeutic tool. This review retrospects the history of ultrasound, the chemistry of functionalized agents and summarizes recent advancements of functional micro/nanobubbles as US contrast agents in preclinical and trans-clinical research. Latest ultrasound-based treatment modalities in association with functional micro/nanobubbles have been highlighted as their great potentials for disease precision therapy. It is believed that these state-of-the-art micro/nanobubbles will become a booster for ultrasound medicine and visualizable guidance to serve future human healthcare in a more comprehensive and practical manner.

The development of endoscopy, microscopy, and image guidance system provided the impetus for the adoption of minimally invasive surgery (MIS) techniques in the management of spinal trauma patients. The underlying drive has been an attempt to achieve the functional and biomechanical goals inherent to trauma care but through MIS techniques. Broadly the MIS techniques for spinal trauma can be divided into two categories—fusion and nonfusion methods. Fusion methods include mini-open or keyhole approaches that allow for discectomy and/or corpectomy and cage reconstruction via an anterior/lateral/posterior operative corridor. The nonfusion methods primarily include percutaneous pedicle screw fixation, kyphoplasty, and vertebroplasty, all without placement of bone graft or other attempts at inducing arthrodesis. In this review article, we have stratified the MIS techniques based on the operative corridor used and briefly described the decision-making process, technical nuances, pros, and cons of each technique.

Objective Endovascular procedures are conventionally conducted using two dimensional fluoroscopy. A new technology platform, Fiber Optic RealShape (FORS), has recently been introduced allowing real time, three dimensional visualisation of endovascular devices using fiberoptic technology. It functions as an add on to conventional fluoroscopy and may facilitate endovascular procedures. This first in human study assessed the feasibility of FORS in clinical practice. Methods A prospective cohort feasibility study was performed between July and December 2018. Patients undergoing (regular or complex) endovascular aortic repair (EVAR) or endovascular peripheral lesion repair (EVPLR) were recruited. FORS guidance was used exclusively during navigational tasks such as target vessel catheterisation or crossing of stenotic lesions. Three types of FORS enabled devices were available: a flexible guidewire, a Cobra-2 catheter, and a Berenstein catheter. Devices were chosen at the physician's discretion and could comprise any combination of FORS and non-FORS devices. The primary study endpoint was technical success of the navigational tasks using FORS enabled devices. Secondary study endpoints were user experience and fluoroscopy time. Results The study enrolled 22 patients: 14 EVAR and eight EVPLR patients. Owing to a technical issue during start up, the FORS system could not be used in one EVAR. The remaining 21 procedures proceeded without device or technology related complications and involved 66 navigational tasks. In 60 tasks (90.9%), technical success was achieved using at least one FORS enabled device. Users rated FORS based image guidance “better than standard guidance” in 16 of 21 and “equal to standard guidance” in five of 21 procedures. Fluoroscopy time ranged from 0.0 to 52.2 min. Several tasks were completed without or with only minimal X-ray use. Conclusion Real time navigation using FORS technology is safe and feasible in abdominal and peripheral endovascular procedures. FORS has the potential to improve intra-operative image guidance. Comparative studies are needed to assess these benefits and potential radiation reduction.

OBJECTIVE A major obstacle to improving bedside neurosurgical procedure safety and accuracy with image guidance technologies is the lack of a rapidly deployable, real-time registration and tracking system for a moving patient. This deficiency explains the persistence of freehand placement of external ventricular drains, which has an inherent risk of inaccurate positioning, multiple passes, tract hemorrhage, and injury to adjacent brain parenchyma. Here, the authors introduce and validate a novel image registration and real-time tracking system for frameless stereotactic neuronavigation and catheter placement in the nonimmobilized patient. METHODS Computer vision technology was used to develop an algorithm that performed near-continuous, automatic, and marker-less image registration. The program fuses a subject’s preprocedure CT scans to live 3D camera images (Snap-Surface), and patient movement is incorporated by artificial intelligence–driven recalibration (Real-Track). The surface registration error (SRE) and target registration error (TRE) were calculated for 5 cadaveric heads that underwent serial movements (fast and slow velocity roll, pitch, and yaw motions) and several test conditions, such as surgical draping with limited anatomical exposure and differential subject lighting. Six catheters were placed in each cadaveric head (30 total placements) with a simulated sterile technique. Postprocedure CT scans allowed comparison of planned and actual catheter positions for user error calculation. RESULTS Registration was successful for all 5 cadaveric specimens, with an overall mean (± standard deviation) SRE of 0.429 ± 0.108 mm for the catheter placements. Accuracy of TRE was maintained under 1.2 mm throughout specimen movements of low and high velocities of roll, pitch, and yaw, with the slowest recalibration time of 0.23 seconds. There were no statistically significant differences in SRE when the specimens were draped or fully undraped (p = 0.336). Performing registration in a bright versus a dimly lit environment had no statistically significant effect on SRE (p = 0.742 and 0.859, respectively). For the catheter placements, mean TRE was 0.862 ± 0.322 mm and mean user error (difference between target and actual catheter tip) was 1.674 ± 1.195 mm. CONCLUSIONS This computer vision–based registration system provided real-time tracking of cadaveric heads with a recalibration time of less than one-quarter of a second with submillimetric accuracy and enabled catheter placements with millimetric accuracy. Using this approach to guide bedside ventriculostomy could reduce complications, improve safety, and be extrapolated to other frameless stereotactic applications in awake, nonimmobilized patients.

Leadless pacemakers have become an effective alternative to conventional transvenous pacemakers to prevent the risk of lead failure, pocket complications, and iatrogenic tricuspid regurgitation. The current transcatheter approach for tricuspid valve repair can limit the implantation of these devices, unless the procedure is performed with appropriate image guidance. We present the case of a patient with severe tricuspid regurgitation secondary to pacemaker lead impingement who, despite the implantation of a tricuspid clip, received a leadless pacemaker. The procedure was successfully guided by transthoracic echocardiography, an alternative to transesophageal or intracardiac echocardiography. Résumé: Les stimulateurs cardiaques sans électrodes sont devenus une solution de rechange efficace aux stimulateurs transveineux classiques pour prévenir le risque de défaillance des électrodes, les complications liées à la loge et la régurgitation tricuspidienne iatrogène. L'approche actuelle de réparation de la valve tricuspide par cathétérisme peut empêcher l'implantation de ces dispositifs, à moins que l'intervention ne soit réalisée avec un guidage par image approprié. Nous présentons le cas d'un patient ayant une régurgitation tricuspidienne grave consécutive à la compression des électrodes d'un stimulateur cardiaque qui, malgré l'implantation d'un clip tricuspide, a reçu un stimulateur cardiaque sans électrodes. L'intervention a été guidée avec succès au moyen d'une échocardiographie par voie transthoracique, une solution de rechange à l’échocardiographie transœsophagienne ou intracardiaque.

To investigate the risk factors of complications in lung cancer patients after CT image-guided percutaneous lung biopsy (PTNB), in this study, 110 patients admitted to Xixi Hospital from January 30, 2017 to June 30, 2019 were selected for PTNB, and the basic characteristic information, lesion diameter, number of needle penetration, depth of needle penetration, physiological results of biopsy, postoperative concurrent symptoms, and success rate of biopsy were recorded. In addition, multivariate Logistic regression model (MLRM) was adopted to explore the correlation between various correlated characters and concurrent symptoms. The results showed that the biopsy pathological results were 53 cases of adenocarcinoma, 31 patients with squamous cell carcinoma, 8 patients with thymic carcinoma, 7 patients with small cell carcinoma and 11 patients with lymph carcinoma, and the success rate of needle biopsy was 100% by comparison with the final diagnosis. Among them, 35 patients developed pneumothorax symptoms postoperatively with a complication rate of 31.82%, 22 patients developed hemoptysis postoperatively with a complication rate of 20%, and 6 patients developed infection with a complication rate of 5.45%. The results of regression analysis showed that pneumothorax and hemoptysis were positively correlated with the number of de needles (P < 0.05), and negatively correlated with lesion diameter (P < 0.05). In addition, pneumothorax was also significantly positively correlated with age (P < 0.05), and infection was significantly positively correlated with the number of puncture needles (P < 0.05). Therefore, the main complications after PTNB are pneumothorax and hemoptysis, the high risk factors associated with pneumothorax include lesion diameter, number of puncture needles and age, the high risk factors associated with hemoptysis include lesion diameter and number of puncture needles, and the risk factors associated with infection are number of puncture needles.

Purpose To evaluate intrafractional head motion (IFM) in patients who underwent intracranial stereotactic radiosurgery with the ExacTrac X-ray system (ETX) and a frameless mask. Methods A total of 143 patients who completed a pre-treatment examination for IFM were eligible for this study. The frameless mask type B R408 (Klarity Medical & Equipment Co., Ltd., Guangzhou, China), which covers the back of the head, and the entire face, was used for patient immobilization. After the initial 6D correction and first X-ray verification (IFM1), X-ray verification was performed every 3 min for a duration of 15 min. The IFMp (2 ≤ p ≤ 6) was calculated as the positional difference from IFM1. In addition, the inter-phase IFM (IP-IFM) and IFMm were calculated. The IP-IFM was defined as |IFMp − IFMp-1|, and IFMm as the difference between the values after all patients were asked to move their heads intentionally with the frameless mask on. Results Both translational IFMp and IP-IFM exceeded 1 mm for a single patient, whereas, for all patients, the translational IFMm values were kept to within 1 mm in all directions. The proportions of the rotational IFMp, IP-IFM, and IFMm values within 0.5° were greater than 94.4%, 98.6%, and 90.2% for all of the rotational axes, respectively. Conclusions A frameless mask achieved highly accurate patient positioning in combination with ETX and a 6°-of-freedom robotic couch; however, a deviation over 1 mm and 0.5° was observed with low frequency. Therefore, X-ray verification and correction are required during treatment.

Highlights • Radiotherapy is a suitable option for adjuvant treatment of unresectable SSCC. • The radiotherapy dose was 55 Gy in 20 fractions. • Case report details include patient setup and radiotherapy treatment plan. • The patient remains disease free at 18-months post treatment., Subungal squamous cell carcinoma (SSCC) is a rare malignancy of the nail bed. We present the case of a woman diagnosed with a SSCC of the right thumb. Initial management consisted of surgically excision followed by adjuvant radiotherapy due to a positive bone margin. We describe the patient set-up, immobilisation technique, target volume delineation, radiotherapy planning, fractionation schedule, image guidance and patient outcomes.

Introduction: Endoscopic third ventriculostomy (ETV) is performed by neurosurgeons around the world for the management of hydrocephalus. ETV has been associated with multiple complications, the most significant being iatrogenic injury to the fornix. We aim to establish the fact that the use of image guidance while planning a trajectory can reduce the incidence of complications as it significantly alters the usual approach for ETV, i.e., the coronal burr hole can be useful for young neurosurgeons to overcome the learning curve associated with the procedure. Materials and Methods: This is a prospective, observational study conducted at Liaquat National Hospital. In this study, 43 patients were included who underwent ETV for hydrocephalus. Complications were divided into three major groups: arterial hemorrhage, venous hemorrhage, and injury to neural structures (fornix, hypothalamus, and oculomotor nerve). The data were compared with studies showing the complications of ETV with and without usage of image guidance. Results: Among the 43 patients who underwent ETV with image guidance, only two patients (4.65%) had iatrogenic fornix contusions. Neither of them developed memory impairment. None of the patients (0%) encountered other major iatrogenic complications, including injury to the mammillary body, basilar artery, or oculomotor nerve. Conclusion: The use of image guidance can reduce trajectory-related complications, including hemorrhage and iatrogenic injuries to the fornix. This study showed that the altered trajectory was beneficial in avoiding major neurological structures while introducing an endoscope through the cortex into the ventricular system.

Therapeutic nanomaterials serve as an important platform for drug delivery under image guidance. Despite significant growth and broad applications, their design specifics remain a subject of continued interest primarily due to multifunctional factors involved, ranging from nanomaterial properties, imaging modalities, and therapeutic agents to activation strategies. This review article summarizes key findings on their design characteristics with a particular interest in strategies developed for therapeutic activation (release). First, their activation can be controlled using either an endogenous factor including low pH and glutathione or an external stimulation by light, ultrasound, or electromagnetic field. The former is passively controlled from a spatiotemporal aspect compared to the latter, which is otherwise actively controlled through drug linker photolysis, nanomaterial disassembly, or gate opening. Second, light stimulation serves a most notable strategy due to its essential role in controlled drug release, photothermal activation (hyperthermia), and photodynamic production of reactive oxygen species (ROS). Third, some of those activation strategies that rely on ultrasound, photothermal, photoacoustic, magnetic field, or X-ray radiation are dually functional due to their role in imaging modalities. In summary, this review article presents recent advances and new insights that pertain to nanotherapeutic delivery systems. It also addresses their technical limitations associated with tissue penetration (light), spatial resolution (ultrasound, hyperthermia), and occurrence of cellular resistance (ROS).

Background and purposeWhen treating patients for esophageal cancer (EC) with photon or proton radiotherapy (RT), breathing motion of the target and neighboring organs may result in deviations from the planned dose distribution. The aim of this study was to evaluate the magnitude and dosimetric impact of breathing motion. Results were based on comparing weekly 4D computed tomography (4D CT) scans with the planning CT, using the diaphragm as an anatomical landmark for EC.Material and methodsA total of 20 EC patients were included in this study. Diaphragm breathing amplitudes and off-sets (changes in position with respect to the planning CT) were determined from delineated left diaphragm structures in weekly 4D CT-scans. The potential dosimetric impact of respiratory motion was shown in several example patients for photon and proton radiotherapy.ResultsVariation in diaphragm amplitudes were relatively small and ranged from 0 to 0.8 cm. However, the measured off-sets were larger, ranging from -2.1 to 1.9 cm. Of the 70 repeat CT-scans, the off-set exceeded the ITV-PTV margin of 0.8 cm during expiration in 4 CT-scans (5.7%) and during inspiration in 13 CT-scans (18.6%). The dosimetric validation revealed under- and overdosages in the VMAT and IMPT plans.ConclusionsDespite relatively constant breathing amplitudes, the variation in the diaphragm position (off-set), and consequently tumor position, was clinically relevant. These motion effects may result in either treatments that miss the target volume, or dose deviations in the form of highly localized over- or underdosed regions.

CT-guided treatment delivery can improve target localization in mediastinal lymphoma patients treated with "butterfly" intensity-modulated radiotherapy and deep-inspiration breath hold. Although daily CT imaging adds additional radiation exposure, its use may be justified given the greater normal tissue sparing enabled by PTV margin reduction.

Introduction Ultrasound (US) guidance of the prostate has long been conducted using a transabdominal (TA) approach. More recently, a transperineal (TP) approach has been made available for image guidance. Our aim was to determine if both methods produced similar alignments within the same patients. Materials and methods We utilized two clinical US image guidance (IG) systems (Elekta Clarity and Best BAT). The B-mode Acquisition and Targeting USIG system is a bi-planar, so-called 2.5D USIG system, that is acquired TA. Clarity is a 3D US system that generates a volumetric 3D US data set and US-derived IG contours that are coregistered to the planning CT images. The probe is oriented in the sagittal plane against the perineum (TP). After positioning the patient for treatment using the TP USIG, we maintained the position defined by Clarity tracking and then acquired a TA-based USIG. The two US-based methods of localizing the prostate (TA vs TP) were compared via Bland-Altman (BA) statistical analysis to determine if there was alignment agreement between methods. Results The BA test for all 101 patients, 2093 fractions resulted in 95% confidence intervals (upper and lower limits of the BA test) of 0.6 mm in LR, 0.9 mm in AP and 1.0 mm in SI. The bias between the two systems was calculated as 0.03, 0.02, and 0.03 mm in LR, AP, and SI. Conclusions Both systems resulted in statistically equivalent targeting positions for the prostate. Because of the unique intrafraction, real-time motion tracking capability of the TP system, this solution represents a unique extension to the previously reported clinical benefits of a TA approach by providing assurance of the prostate remaining in the treatment field during beam-on.

Background Musculoskeletal pain is a debilitating problem treated with image-guided corticosteroid injections. During the COVID-19 pandemic, multiple societies issued caution statements because of the unknown effect of corticosteroids on the patient’s immune system. The purpose is to determine if image-guided corticosteroid injections administered during the COVID-19 lockdown phase were associated with a higher infection rate compared to the general population. Materials and methods In a prospective study, patients undergoing image-guided corticosteroid injections for pain management during the lockdown phase between April 15 and May 22, 2020, were enrolled. One month after the injection, patients were surveyed by telephone for any COVID-19-related symptoms, and the electronic medical record (EMR) was reviewed for symptoms and test results. Results Seventy-one subjects were recruited, 31 (44%) females, 40 (56%) males, ages 58 ± 17 (20–92) years. Follow-up was available in 66 (93%) of subjects, 60 (91%) by phone survey and EMR, 6 (9%) by EMR only, 45 ± 22 (19–83) days after injection. One (1/66, 1.52%; 95% CI 0.04–8.2%) 25-year-old male subject developed symptomatic infection 19 days after a tibiotalar injection. The prevalence of COVID-19 cases in the state of Massachusetts was 0.91% (62,726/6,892,503) during the study period. There was no significant difference in the rate of occurrence of new cases of COVID-19 infection between the corticosteroid injection group and the general population (p = 0.44). Conclusion Image-guided corticosteroid injections for pain management performed during the lockdown phase of the COVID-19 pandemic were not associated with a higher infection rate compared to the general population.

Purpose To report on the use of surface guided imaging during frameless intracranial stereotactic radiotherapy with automated delivery via HyperArcTM (Varian Medical Systems, Palo Alto, CA). Methods All patients received intracranial radiotherapy with HyperArcTM and were monitored for intrafraction motion by the AlignRT® (VisionRT, London, UK) surface imaging (SI) system. Immobilization was with the EncompassTM (Qfix, Avondale, PA) aquaplast mask device. AlignRT® log files were correlated with trajectory log files to correlate treatment parameters with SI reported offsets. SI reported offsets were correlated with gantry angle and analyzed for performance issues at non‐zero couch angles and during camera‐pod blockage during gantry motion. Demographics in the treatment management system were used to identify race and determine if differences in SI reported offsets are due to skin tone settings. Results A total of 981 fractions were monitored over 14 months and 819 were analyzed. The median AlignRT® reported motion from beginning to the end of treatment was 0.24 mm. The median offset before beam on at non‐zero couch angles was 0.55 mm. During gantry motion when camera pods are blocked, the median magnitude was below 1 mm. Median magnitude of offsets at non‐zero couch angles was not found to be significantly different for patients stratified by race. Conclusions Surface image guidance is a viable alternative to scheduled mid‐treatment imaging for monitoring intrafraction motion during stereotactic radiosurgery with automated delivery.

Intraoperative imaging has become one of the most important adjuncts in neurosurgery, especially in the surgical treatment of intra-axial tumors. Navigation and intraoperative magnetic resonance imaging have limitations, and intraoperative ultrasonography (IOUS) has emerged as a versatile and multifaceted alternative. With technological advances in ultrasound scanners and newer multifunctional probes, the potential of IOUS is increasingly being utilized in the resection of tumors. The addition of image guidance to IOUS has exponentially increased the power of this technique. Navigated ultrasonography (nUS) can now overcome many of the limitations of conventional standalone two-dimensional ultrasonography. In this pictorial essay, we outline our nUS technique (both two- and three-dimensional) for the resection of intra-axial tumors with illustrated examples highlighting the various steps and corresponding benefits of the technique.

The objective of this retrospective study is to more fully understand the optimal strategy to manage spinal arteriovenous (AV) shunts. This study included a cohort of 35 patients with a diagnosis of spinal AV shunts who were treated over the past 10 years at a single institute. Angiographic diagnosis of intramedullary AV malformations (IM-AVM), perimedullary AV fistulas (PM-AVF), dural AV fistulas (D-AVF), or epidural AV fistulas (ED-AVF) was carefully made, and the microsurgical or endovascular strategy for them was determined at the interdisciplinary meeting consisting of neurospinal surgeons and endovascular specialists. Endovascular surgery was first considered whenever safely possible. Microscopic direct surgery using intraoperative image guidance was considered for cases in which endovascular access was challenging or not safely possible. Combined treatment was another option. The clinical condition was assessed using the modified Rankin scale (mRS). Seventeen of 35 cases were treated with microscopic direct surgery, 13 cases with endovascular surgery, and the remaining five cases with the combination. Complete angiographic obliteration was achieved in 30 of 35 cases (85.7%). Although residual AV shunts was recognized in 3 cases of IM-AVM, 1 case of PM-AVF and 1 case of ED-AVF, no angiographic recurrence was present with an average postoperative follow-up period of 44 months. The average mRS before surgery was 2.37 and significantly improved to 1.94 at the most recent follow-up. Interdisciplinary collaboration between neurospinal surgeons and endovascular specialists should be standard to achieve safe and successful outcomes in treating such rare and difficult spinal disorders.