Real-time Fluoroscopic Guidance Research Articles

Cystic Plate Approach Combined with Indocyanine Green（ICG） Fluorescence in Laparoscopic Anatomical Hepatectomy.

The in-depth understanding of the fine anatomy of the liver has promoted the development of modern liver surgery. With the rapid popularity of laparoscopic hepatectomy, the membrane structure of the liver and its ability to dissect the intra- and extra-hepatic vascular system more conveniently and accurately has been gradually emphasized. Exploring the value of extrahepatic sheath dissection of the hepatic pedicle in minimally invasive anatomical hepatectomy with cystic plate approach. This study aims to assess the benefits of integrating the cystic plate approach with real-time guided laparoscopic anatomical hepatectomy, in comparison with conventional laparoscopic anatomical hepatectomy. Based on the theory of cystic plate and hepatic portal plate, we have pioneered the fluorescence real-time guided cystic plate approach in hepatectomy. The article focuses on the anatomical knowledge and technical difficulties of anatomical hepatectomy with fluoroscopic laparoscopic cystic plate approach and explores the safety and practicality of the cystic plate approach in laparoscopic anatomical hepatectomy. Additionally, a retrospective cohort study was also conducted to compare the operation time, intraoperative blood loss, and postoperative complications between the cystic plate approach and the conventional approach during fluoroscopic laparoscopic hepatectomy. A total of 38 patients who met the inclusion criteria underwent laparoscopic hepatectomy between January 2019 and November 2022. No significant disadvantages were found in terms of operation time and intraoperative blood loss during the surgeries. Furthermore, the postoperative indications, including liver function indexes on the first postoperative day, WBC, and the postoperative hospital stay, were also not affected, thus proving the safety of the cystic approach. Importantly, through the cystic plate approach, the target liver pedicle was fully freed, and then the segments to be resected were precisely marked by positive or negative staining, followed by hepatectomy under real-time fluoroscopic guidance. This approach is extremely advantageous in anatomical liver segment resections, especially in right posterior lobe or hemi-hepatectomy, without increasing intraoperative bleeding or postoperative complication rates. This technique allows for easy and safe freeing of the target liver pedicle using membrane structures, and also allows for precise anatomical hepatectomy in combination with real-time fluoroscopic laparoscopic navigation.

Intraprocedural guidance for recanalization of post-thrombotic venous lesions using live overlay of center lines from pre-operative cross-sectional imaging: a preliminary experience

PurposePre-procedural contrast-enhanced CT and MRI imaging is typically acquired prior to deep venous recanalization procedures for post-thrombotic syndrome. This technical note reports the utility of live-overlay of augmented centerlines extracted from pre-procedural CT and MRI imaging in facilitating fluoroscopic-guided recanalization of post-thrombotic venous lesions.Methods and materialsSix patients with pre-procedural CT or MR venography data were incorporated into a commercially available 3D overlay software (Vessel Assist, GE Healthcare, Buc, France) during venous disease interventions for post-thrombotic venous lesions. Procedures were performed on the GE Discovery IGS 740 fluoroscopy system. After manual determination of the vasculature from preprocedural CT or MR, centerlines were created representing the location and trajectory of the vessels. Steps showcasing the creation of centerlines and their representation during overlay with real-time fluoroscopic guidance in these cases are outlined. Time required to cross the post-thrombotic and occlusive venous segments were reviewed.ResultsAll iliocaval recanalization procedures were successfully performed utilizing vessel centerline 3D overlay. In one case where occlusion extended to the femoral vein, mis-registration was identified over the femoral anatomy due to a complex leg rotation compared to pre-procedural imaging. No procedural complications related to utilization of software were noted. Average crossing time for occlusions was 3.4 min (range 1.6–5.2).Conclusion3D overlay with vessel tracking from pre-procedural CT and MRI imaging is technically feasible and assists in catheter navigation for post-thrombotic venous segments. While results from these preliminary experiences support the continued use of this technology, further prospective and comparative evaluation of this technique is warranted to assess for added value in technical success, reductions in procedure time or reductions in radiation exposure.

Single-stage hybrid localization: a combination of bronchoscopic lung mapping followed by post-mapping computed tomographic reconstruction and additional transthoracic needle localization in a cone beam computed tomography room.

Bronchoscopic lung mapping is a multispot dye-marking technique, which should be performed under real-time fluoroscopic guidance and post-mapping computed tomographic reconstruction. This study aimed to investigate the feasibility of lung mapping followed by post-mapping computed tomography (CT) and additional needle localization in a cone bean CT (CBCT) room. Between February 1, 2018 and August 31, 2018, 11 consecutive patients presenting with 14 lung lesions underwent bronchoscopic lung mapping in a CBCT room followed by thoracoscopic surgery. The efficacy and safety of the procedure were assessed through a retrospective chart review. The median size of the pulmonary lesions was 8.1 mm [interquartile range (IQR), 7.2-10.8 mm] with a median depth-to-size ratio (D-S) ratio of 2.43 (IQR, 1.56-2.79). Additional needle localizations were performed in 4 patients, of which 3 and 1 patients underwent dual localization with dye and microcoil and localization with dye only, respectively. The median total localization time was 28 min (IQR, 18-69 min), and the median radiation exposure was 345.0 mGy (IQR, 161.8-486.6 mGy). A total of 8 wedge resections, 5 segmentectomies, and 1 lobectomy were performed. The final pathological diagnoses were as follows: primary lung cancer (n=6), lung metastases (n=4), and benign lung lesions (n=4). No adverse events were observed, and the median length of postoperative stay was 4 days (IQR, 3-5 days). Bronchoscopic lung mapping followed by post-mapping CT and additional needle localization can be performed together in a single examination room equipped with a C-arm CBCT, and the results of localization are contributory to the surgery.

Head-mounted display augmented reality to guide pedicle screw placement utilizing computed tomography.

Augmented reality has potential to enhance surgical navigation and visualization. We determined whether head-mounted display augmented reality (HMD-AR) with superimposed computed tomography (CT) data could allow the wearer to percutaneously guide pedicle screw placement in an opaque lumbar model with no real-time fluoroscopic guidance. CT imaging was obtained of a phantom composed of L1-L3 Sawbones vertebrae in opaque silicone. Preprocedural planning was performed by creating virtual trajectories of appropriate angle and depth for ideal approach into the pedicle, and these data were integrated into the Microsoft HoloLens using the Novarad OpenSight application allowing the user to view the virtual trajectory guides and CT images superimposed on the phantom in two and three dimensions. Spinal needles were inserted following the virtual trajectories to the point of contact with bone. Repeat CT revealed actual needle trajectory, allowing comparison with the ideal preprocedural paths. Registration of AR to phantom showed a roughly circular deviation with maximum average radius of 2.5mm. Users took an average of 200s to place a needle. Extrapolation of needle trajectory into the pedicle showed that of 36 needles placed, 35 (97%) would have remained within the pedicles. Needles placed approximated a mean distance of 4.69mm in the mediolateral direction and 4.48mm in the craniocaudal direction from pedicle bone edge. To our knowledge, this is the first peer-reviewed report and evaluation of HMD-AR with superimposed 3D guidance utilizing CT for spinal pedicle guide placement for the purpose of cannulation without the use of fluoroscopy.

Accuracy of image-guided percutaneous injection into a phantom spinal cord utilizing flat panel detector CT with MR fusion and integrated navigational software

PurposeTo evaluate the accuracy of percutaneous fluoroscopic injection into the spinal cord of a spine phantom utilizing integrated navigational guidance from fused flat panel detector CT (FDCT) and MR datasets....

Interventional radiofrequency ablation: A promising therapeutic modality in the management of malignant biliary and pancreatic duct obstruction.

Background: Malignant biliary and/or pancreatic obstruction has often encountered in the advanced stages of periampullary and cholangicarcinomas. HabibTM Radiofrequency (RF) ablation has been successfully used in the management of various cancers of liver and pancreas. Percutaneous HPB probe (EMcision Ltd, London, UK) is a new addition to this class of tools. It is an endoluminal Radiofrequency (RF) catheter which works on the principle of ablation and induces coagulative necrosis to recanalize the obstructed duct. The aim of this study is to address the technical details of canalization, feasibilities and outcomes of percutaneous endo-luminal Radiofrequency (RF) catheter in patients with unresectable malignancy with obstructed bile and pancreatic duct (PD).Material and Method: A total of 134 patients with inoperable malignant obstruction of biliary and PD underwent RF based percutaneous endoluminal RF ablation in a tertiary referral centre between December 15th, 2010 to August 7th, 2015. This device was used in a sequential manner with an intent to recanalize the obstructed. Following the initial catheter drainage of the duct, subsequent percutaneous endobiliary RF ablation, the metallic stent was placed to recanalize the obstructed bile and PD secondary to unresectable malignancy under real-time fluoroscopic guidance.Results: The percutaneous RF based ablation of obstructed bile duct and PD with metallic stent placement was successfully achieved in 130 (97.01%) cases. The three failures were noted in cases of biliary obstruction whilst, one with PD obstruction. The patency restored in 124 and patients, where the procedure was successfully completed and revealed clinical improvement reported.Conclusion: The percutaneous endoluminal RF based ablation of obstructed duct with metallic stent placement appeared to be a safe, effective procedure and may improve survival in patients with advanced stage cancer presenting with biliary and PD obstruction. Considering the above mentioned evidence, this modality may stand ahead of stenting alone. This could be considered as viable modality in management of such patients where very limited treatment options are available.

Intraventricular injectable tumor model for neuroendoscopic surgery: Laboratory Study

Abstract Intraventricular tumors present difficult challenges to the neurosurgeon. Neurosurgeons have begun to explore the possibilities of the endoscope in the complete resection of solid intraventricular tumors. The learning curve is considered steep when dealing with such lesions endoscopically. The aim of this study was to develop a laboratory training model for pathological intraventricular neuroendoscopic surgery. Thirty formalin-fixated, latex-injected cadaveric heads were used. The contrast-enhancing tumor polymer, Stratathane resin ST-504 derived polymer (SRSDP), was injected into the lateral ventricle via Frazer’s point under direct endoscopic visualization and real-time fluoroscopic guidance. Neurosurgeon participants at a ventricular endoscopic course then performed an endoscopic approach to the intraventricular tumor model lesion via an ipsilateral frontal burr hole. The properties of the SRSDP mixture could be manipulated through varying concentrations of source materials in order to achieve a desired consistency and allow for piecemeal resection. Tumor could be injected into the lateral and third ventricles. The tumor model allowed participants to compare both normal and pathological endoscopic anatomy in the one specimen. Our novel injectable tumor model can assist neurosurgeons preparing themselves for the challenges associated with a piecemeal resection of a solid lesion in the lateral or third ventricle.

Safer lung biopsy techniques: fewer patients with pneumothorax, fewer chest tube insertions.

Image guided transthoracic lung biopsy is a widely accepted technique for the workup of lung lesions (1). Screening for lung cancer and the growing need for research biopsy samples will continue to increase the demand for image guided lung biopsy (2,3). Technical aspects of the procedure have evolved over the years and will continue to change. In the early days, lung biopsies were performed under fluoroscopic guidance. With the widespread use of cross sectional imaging and multidetector CTs, most centers in the US have shifted their practice to performing lung biopsies under CT guidance (4). Others have experimented with C-arm cone-beam computed tomography (CBCT) to combine advantages of real-time fluoroscopic guidance with accuracy of cross sectional imaging (5-7).

Safety of Lumbar Spine Radiofrequency Procedures in the Presence of Posterior Pedicle Screws: Technical Report of a Cadaver Study

To determine whether the thermal energy associated with lumbar spine radiofrequency neurotomy (RFN) performed near titanium and stainless steel pedicle screws is conducted to the pedicle screws or adjacent tissues, or both, thus introducing potential for thermal damage to those tissues. Cadaver study. Cadaver laboratory equipped with fluoroscopy, surgical spine implements, and radiofrequency generator. No live human subject; a fresh frozen (and thawed) cadaver torso was used for the study. Titanium and stainless steel pedicle screws were placed in the lumbar spine of a fresh frozen cadaver torso with real-time fluoroscopic guidance. Conventional RFN cannula placement was performed at the level of pedicle screws and a control (nonsurgically altered) lumbar level. Neurotomy was performed with conventional radiofrequency lesioning parameters. Temperatures were recorded at multiple sites through thermistor probes. Direct contact of the radiofrequency cannula with the pedicle screws during conventional RFN produced a substantial increase in temperature in the surrounding soft tissues. A small increase in temperature occurred at the same sites at the control level. Titanium and stainless steel pedicle screws are capable of sustaining large increases in temperature when the radiofrequency probe comes in contact with the screw. These results are suggestive that pedicle screws could serve as a possible source of tissue heating and thermal injury during RFN.

Treatment of supratentorial spontaneous intracerebral hemorrhage using image-guided minimally invasive surgery: Initial experiences of a flat detector CT-based puncture planning and navigation system in the angiographic suite.

The intracerebral hemorrhage drainage through minimally invasive approach is emerging as an alternative for traditional craniotomy, due to its improved survival rate and reduced complication rate. In this study, we investigated the feasibility and safety of a flat detector CT-based puncture planning and navigation system for minimally invasive hematoma drainage on patients with intracerebral hemorrhage. The minimally invasive hematoma drainage was performed on 21 hypertensive patients with intracerebral hemorrhage in the angiographic suite with the guidance of a flat detector CT-based puncture planning and navigation system. This system is integrated in the angiographic machine, and was used for 1) planning the needle path based on a preprocedural flat detector CT scan, 2) advancing the catheter with real-time fluoroscopic guidance, and 3) confirming the procedure outcome based on an immediate postprocedural flat detector CT. The surgery efficiency, accuracy, and the treatment outcome were measured and compared with the published data. All procedures were successfully completed with the catheter placed 4 ± 1 mm from the planned position. The average surgery time was 40 ± 7 minutes. The volume of the hematoma was reduced to 28 ± 4% of the original volume. The Glasgow Coma Scale score was significantly improved from 10 ± 1 at the admission to 14 ± 1 at the discharge. The Extended Glasgow Coma Scale score also improved from 5 ± 1 at the discharge to 6 ± 1 at the 6-month follow-up. No major complication, rebleeding, and mortality were observed in this study. This flat detector CT-based needle guidance system provided a feasible, convenient, and safe way to perform the puncture and drainage of brain hematoma in the angiographic suite.

Cervical Epidural Steroid Injections for the Treatment of Cervical Spinal (Neck) Pain

Cervical epidural steroid injections (CESI) are an accepted treatment for neck pain with a radicular component, and may be accomplished by using either transforaminal (CTFESI) or interlaminar (CILESI) approaches. CESIs are routinely performed using real-time fluoroscopic-guidance in conjunction with the injection of water soluble, iodine-based contrast media to enhance visualization of intravascular injections. Digital subtraction angiography (DSA) imaging is an adjuvant to fluoroscopic methods for visualizing blood vessels while performing spinal injections. However, as with any neuraxial procedure, various complications associated with CESIs have been reported. Complications are directly associated with the technical procedures of CESIs. Particulate steroids may have a prolonged duration of action but non-particulate steroids are safer for CESIs. Blunt-beveled needles are less likely than sharp-beveled needles to penetrate blood vessels to cause bleeding complications during CTFESI procedures. Small doses of local anesthetics appear to be safe and assist in identifying intravascular injections previously overlooked by conventional techniques.

Frameless multimodal image guidance of localized convection-enhanced delivery of therapeutics in the brain

IntroductionConvection-enhanced delivery (CED) has been shown to be an effective method of administering macromolecular compounds into the brain that are unable to cross the blood-brain barrier. Because the administration is...

Initial experience of percutaneous transthoracic needle biopsy of lung nodules using C-arm cone-beam CT systems

To describe our initial experience with percutaneous transthoracic biopsy (PCNB) of lung nodules using C-arm cone-beam CT (CBCT). Seventy-one consecutive patients with lung nodules of 30 mm or smaller underwent CBCT-guided PCNB using a coaxial cutting needle. We evaluated the procedure time, coaxial introducer dwell time, the numbers of pleural passages, coaxial introducer repositionings and CT acquisitions, as well as the technical success rate and radiation doses. Diagnostic accuracy, sensitivity, specificity and incidence of complications were also evaluated. PCNB was performed for 71 nodules: 63 solid, 6 part-solid and 2 ground-glass nodules. The procedure time, coaxial introducer dwell time, numbers of pleural passages, coaxial introducer repositionings and CT acquisitions were 17.9+/-5.9 min, 8.7+/-3.8 min, 1.1+/-0.4, 0.2+/-0.5 and 2.9+/-0.7, respectively. The technical success rate was 100% and the radiation dose was 272+/-116 mGy. Thirty-six nodules (50.7%) were diagnosed as malignant, 25 (35.2%) as benign and 10 (14.1%) as indeterminate. Diagnostic accuracy, sensitivity, specificity and incidence of complications were 98.4%, 97%, 100% and 38%, respectively. Complications included pneumothorax in 18 patients (25.4%), haemoptysis in 10 (14.1%) and chest pain in one (1.4%). Under CBCT guidance, PCNB of lung nodules can be performed accurately, providing both real-time fluoroscopic guidance and CT imaging capabilities.

Image-Guided Robotic Flexible Needle Steering

This paper presents a robotic system for steering under real-time fluoroscopic guidance a flexible needle in soft tissue. Given a target and possible obstacle locations, the computer calculates the flexible needle-tip trajectory that avoids the obstacle and hits the target. Using an inverse kinematics algorithm, the needle base maneuvers required for a tip to follow this trajectory are calculated, enabling a robot to perform controlled needle insertion. Assuming small displacements, the flexible needle is modeled as a linear beam supported by virtual springs, where the stiffness coefficients of the springs can vary along the needle. Using this simplified model, the forward and inverse kinematics of the needle are solved analytically, enabling both path planning and path correction in real time. The needle shape is detected in real time from fluoroscopic images, and the controller commands the needle base motion that minimizes the needle tip error. This approach was verified experimentally using a robot to maneuver the base of a flexible needle inserted into a muscle tissue. Along the 40-mm trajectory that avoids the obstacle and hits the target, the error stayed below the 0.5-mm level. This study demonstrates the ability to perform closed-loop control and steering of a flexible needle by maneuvering the needle base so that its tip achieves a planned trajectory.

Use of gadolinium chelate to confirm epidural needle placement in patients with an iodinated contrast reaction

When performing epidural steroid injections for the management of chronic back pain, imaging guidance and a limited epidurogram improve accuracy of needle placement and ensure appropriate delivery of the injectate into the epidural space. We describe our experience using a gadolinium chelate as an alternative contrast agent for limited epidurography in patients with a history of an iodinated contrast reaction. Thirty-eight of 2,067 (1.8%) epidural steroid injections performed in our department over a 25-month period (December 2003-January 2006) employed gadolinium. All injections were performed in the lumbar spine employing a paramedian interlaminar approach. Procedural notes and patient charts were reviewed to evaluate for immediate or delayed complications related to incorrect intrathecal or intravascular needle placement. A retrospective analysis of selected fluoroscopic spot images was performed to evaluate confidence of epidural needle placement; this analysis compared these spot images against those obtained from age- and gender-matched control patients in whom iodinated contrast was used to confirm needle placement. Real-time fluoroscopic guidance permitted confident visualization of an epidurogram at the time of procedure in all 38 cases as documented in the procedural report, and no procedure resulted in a complication due to incorrect needle placement. Retrospective review of fluoroscopic spot images revealed at least moderate confidence of epidural needle placement by both readers in 29/38 cases (76.3%). Fluoroscopic spot images obtained using gadolinium yielded significantly less confidence than images obtained in control patients whose procedures were performed using iodinated contrast (P < 0.01). However, operators were sufficiently confident in needle placement based on real-time fluoroscopic images (not available in our subsequent review) to inject anesthestic in all 38 cases, despite the immediate consequences that could result from intrathecal administration. During the same time period, there were 11/2,067 (0.5%) instances of intrathecal needle placement discovered during attempted epidurography despite the use of fluoroscopy for needle guidance and reliance on loss-of-resistance technique. Gadolinium chelate represents a safe and useful alternative contrast agent for confirmation of epidural needle placement in patients with an iodinated contrast allergy.

A posterior parasagittal approach to thoracic paravertebral neural structures with curved cannulae

The clinical value of percutaneous diagnostic and therapeutic interventions in modern spine care has increased in proportion to growing knowledge regarding specific sites and structures responsible for chronic spinal pain. Although the information gained from noninvasive technologies continues to improve, correlation of morphologic abnormalities with clinical symptoms can often only be achieved with target-specific analgesic or provocative testing. Cervical and lumbar percutaneous techniques abound, but relatively little has been published on target-specific approaches to the thoracic paravertebral structures. The anatomic juxtaposition of vital viscera, limited access due to bony structures, and the small volume of the thoracic paravertebral space have likely limited widespread accession of structures specifically involved in thoracic nociception. This report reviews the relevant regional anatomy of the thoracic paravertebral region and basic neurophysiologic principles and rationale for targeting paravertebral structures and outlines a new method of accessing thoracic paravertebral neural structures with curved cannulae and real-time fluoroscopic guidance. Clinical applications and indications are also discussed. This method has permitted the performance of more than 1,000 thoracic percutaneous paravertebral procedures of varying levels of complexity to be performed by the author without a single case of clinically evident or documented pneumothorax. Copyright © 2001 by W.B. Saunders Company

Safe superconducting current discharge for the magnetic stereotaxis system

The Magnetic Stereotaxis System is a unique neurosurgical device designed to provide surgical treatment of regions of the brain normally inaccessible with contemporary techniques. By magnetically propagating a small (approximately 5 mm length, approximately 3 mm diameter) magnetic implant and attached catheter through the brain under near real-time fluoroscopic guidance while referencing preoperative magnetic resonance imaging scans, both precision surgery and drug therapy can be applied to specific sites in the brain while circumventing the blood-brain barrier. Given the high current requirements for the proper operation of the system, a hazard exists in which a coil may fail by either a coil quench or a magnet system shutdown. A silicon controlled rectifier switch and varistor combine to circumvent this threat by controlling the current discharge, thereby preventing damage to the cryogenic system while simultaneously protecting the patient. Analysis reveals that of the failures that may occur in the volume occupied by the brain, a field direction variation of up to 150 at a magnitude of 0.10-0.15 T results for 70% of the casts, 0.15-0.20 T for 50%, 0.20-0.25 T for 25%, and 0.25-0.30 T for 5%. In no circumstance does the force magnitude increase.