Intraoperative Image Guidance Research Articles

Zero-Crosstalk Tumor-Targeting Ratiometric Near-Infrared γ-Glutamyltranspeptidase Probe for Fluorescent-Guided Surgical Resection of Orthotopic Hepatic Tumor.

The challenge of "false positive" signals significantly complicates tumor localization and surgical resection, which are pivotal for successful tumor surgeries. Therefore, the development of a method for preoperative tumor localization and intraoperative margin determination holds considerable promise for improving surgical outcomes. In this study, a zero-crosstalk ratiometric tumor-targeting near-infrared (NIR) fluorescent probe was developed for precise cancer diagnosis and intraoperative navigation via NIR fluorescence imaging. This probe integrates a tumor-targeting moiety that selectively homes in on hepatocellular carcinoma cells and exhibits a highly sensitive ratiometric response to γ-glutamyltranspeptidase (GGT), characterized by a substantial emission shift from 830 to 650 nm. This unique NIR ratiometric emission property significantly enhances its effectiveness in early diagnosis and imaging-guided surgery resection. Furthermore, this zero-crosstalk probe successfully monitors GGT activity in blood, cells, and in vivo, endowing its potential for early cancer diagnosis in the clinic. Due to its efficient targeting and sensitive in situ response to GGT in both subcutaneous tumors and orthotopic hepatic tumors, the probe exhibits accurate detection capability for hepatic tumors. Additionally, by leveraging zero-crosstalk ratiometric NIR fluorescence imaging, this tumor-targeting probe can serve as a sprayable tool for delineating tumor margins with precision, thereby furnishing real-time intraoperative imaging guidance during tumor resection surgery.

The role of hyperaccuracy CT three-dimensional reconstruction technology in partial nephrectomy for completely endophytic renal cell carcinoma: A retrospective propensity-matched cohort study.

To compare the clinicopathological, perioperative, functional, and oncological outcomes of completely endophytic renal cell carcinoma (RCC) patients who underwent partial nephrectomy (PN) with or without preoperative hyperaccuracy CT three-dimensional (HACT3D) reconstruction. A retrospective cohort study was conducted on 154 completely endophytic RCC patients treated with PN at our medical center from January 2018 to December 2023. Patients were divided into two groups based on whether they received preoperative HACT3D reconstruction. To control for selection bias, we implemented 1:1 propensity score matching based on baseline characteristics. In the original cohort, 47 patients in the HACT3D group had higher RENAL scores (P=0.014) and PADUA scores (P=0.012). After matching, each group contained 47 RCC patients with no significant baseline differences (P>0.05). In the matched cohort, patients in the HACT3D group had significantly shorter warm ischemia time (WIT) (22.3 vs. 26.7min, p<0.001), shorter total length of hospital stay (LOS) (10.0 vs. 11.6 days, p=0.012), shorter postoperative LOS (5.8 vs. 7.3 days, p=0.003), and higher trifecta achievement rate (83.0% vs. 36.2%, p<0.001). Among functional variables, patients in the HACT3D group exhibited a smaller increase in postoperative serum creatinine (SCR) (7.5 vs. 16.5μmol/L, p=0.012), and a smaller decrease in postoperative estimated Glomerular Filtration Rate (eGFR) (-6.9 vs. -14.1mL/min/1.73m2, p=0.011). No significant differences were found in pathological outcomes and prognosis between the two groups (p>0.05). For completely endophytic RCC patients, HACT3D reconstruction can assist clinicians in performing precise parameter measurements, designing personalized surgical approaches, and providing intraoperative image guidance.

Cutting Edge Microscopic Intraoperative Tissue Assessment for Guidance in Oncologic Surgery: A Systematic Review of the Role of Optical Coherence Tomography.

There is a demand for intraoperative diagnostic support and image guidance in oncological surgery. Novel techniques can provide images similar to histopathological slides within a few minutes. Optical coherence tomography (OCT) and full-field OCT (FF-OCT) provide images with resolution greater than a hundred micrometers without the need for exogenous contrast agents or specimen staining. The aim of this systematic review was to assess the current clinical applications of OCT and dynamic cell imaging (DCI) in oncologic surgery, examining the translation challenges and proposing perspectives for improving future clinical applications. The study adhered to the PRISMA guidelines. PubMed, Google Scholar, and ClinicalTrials.gov were searched up to July 2024. Manuscripts reporting data on OCT and (D)-FF-OCT application in oncologic surgery were included in the qualitative analysis. Thirty-one studies met the inclusion criteria. Most were from the fields of dermatologic (25.8%) and breast cancer (29%) surgery, followed by prostate and bladder (9.6%), ovarian (9.6%), head and neck (6.4%), gastrointestinal (6.4%), hepato-biliary (3.2%), and general surgery (9.6%). The majority of articles focused on FF-OCT and DCI (80.6%). Compared with the gold standard of final pathology, the OCT sensitivity ranged between 66.7 and 94%, the specificity between 64 and 100%, and the accuracy between 73 and 96%. The medical use of OCT has expanded from ophtalmology to other fields including gastroenterology and oncology and, with techniques such as FF-OCT and DCI, can enable rapid intraoperative diagnosis beyond classic histopathology.

ADVANCING PRECISION

Augmented reality (AR) technology is revolutionizing spine surgery, offering unprecedented intraoperative image guidance and enhancing patient safety, particularly in complex procedures. This presentation explores the expanding applications of AR in spinal surgery, highlighting recent technological advances that have transformed surgical practices. In addition to improving surgical precision and accuracy, AR provides real-time visualization of critical anatomical structures, aiding in navigation and decision-making during intricate spinal procedures. This presentation will delve into the benefits that AR brings compared to classical techniques, including enhanced visualization, improved spatial awareness, and reduced radiation exposure for both patients and surgical teams. By overlaying virtual information onto the surgeon’s view of the patient, AR facilitates a more intuitive understanding of complex spinal anatomy and pathology, leading to optimized surgical outcomes. Furthermore, this session will cover the diverse applications of AR in a range of spinal conditions operated in Royal Hallamshire Hospital, Sheffield, UK - including spinal tumors, calcified disc herniation, spinal CSF-venous fistula etc. By showcasing the benefits of AR technology across various pathologies, this presentation aims to underscore its transformative potential in advancing spinal surgical care.

Advanced tractography-guided laser ablation of a perirolandic long-term epilepsy-associated tumor: illustrative case.

Microsurgical resection of drug-resistant epilepsy-associated perirolandic lesions can lead to postoperative motor impairment. Magnetic resonance imaging (MRI)-guided laser interstitial thermal therapy (MRgLITT) has emerged as a less invasive alternative, offering reduced surgical risks and improved neurological outcomes. Electrophysiological tools routinely used for motor mapping in resective microsurgery are incompatible with intraoperative MRI. The utilization of advanced neuroimaging adjuncts for eloquent brain mapping during MRgLITT is imperative. The authors present the case of a 17-year-old athlete who underwent MRgLITT for a perirolandic long-term epilepsy-associated tumor (LEAT). They performed probabilistic multi-tissue constrained spherical deconvolution (MT-CSD) tractography to delineate the corticospinal tract (CST) for presurgical planning and intraoperative image guidance. The CST tractography was integrated into neuronavigation and MRgLITT workstation software to guide the ablation while monitoring the CST throughout the procedure. The integration of CST tractography into neuronavigation workstation planning and laser ablation workstation thermoablation is feasible and practical, facilitating complete ablation of a deep-seated perirolandic LEAT while preserving motor function. Probabilistic MT-CSD tractography enhanced MRgLITT planning as well as intraprocedural CST visualization and preservation, leading to a favorable functional outcome. The limitations of tractography and the predictability of thermal output distribution compared to the gold standard of microsurgical resection merit further discussion. https://thejns.org/doi/10.3171/CASE24139.

Successful placement of a chest wall venous infusion port via persistent left superior vena cava: A case report.

Persistent left superior vena cava (PLSVC) is a rare congenital venous anomaly occurring in approximately 0.3% to 0.5% of the population. The presence of PLSVC complicates central venous catheter placement, increasing procedural risks. This case report describes the successful placement of a chest wall venous infusion port in a patient with PLSVC, offering valuable insights for managing similar cases and ensuring safer clinical outcomes. A 51-year-old female, 3 weeks post-right breast cancer surgery, was admitted for her first adjuvant hemotherapy session. She requested the placement of a venous infusion port due to the prolonged duration of chemotherapy. Imaging studies suggested the presence of PLSVC. Echocardiography revealed a dilated coronary sinus, and subsequent chest computed tomography and angiography confirmed the presence of PLSVC. A chest wall venous infusion port was inserted via the left internal jugular vein. Due to the PLSVC, the catheter was adjusted to ensure proper placement. The patient successfully completed chemotherapy without any complications or discomfort associated with the venous port. Imaging studies, including chest X-ray and computed tomography, confirmed proper port function and catheter positioning, with no evidence of thrombosis, infection, or other related issues. The patient remained in good overall condition throughout the treatment. Detailed preoperative evaluations, intraoperative imaging guidance, and postoperative follow-ups are crucial for the safe and effective management of PLSVC patients undergoing central venous catheter placement.

Optimizing Glioma Resection Outcomes: A Systematic Review of Intraoperative Magnetic Resonance Imaging Guidance in Neurosurgery.

This systematic review evaluates the efficacy of intraoperative magnetic resonance imaging (iMRI) in enhancing glioma resection outcomes within neurosurgical procedures. Given the complexity and variability of gliomas, achieving precise and safe resections is challenging, necessitating the use of advanced imaging techniques like iMRI. This technology provides real-time, high-resolution insights during surgery, allowing for adaptations based on surgical dynamics and brain shifts. Our comprehensive search across multiple databases selected five significant studies that collectively demonstrate the beneficial impact of iMRI. These studies highlight its role in significantly improving the extent of tumor resection and suggest potential enhancements in both immediate and long-term patient outcomes. The findings indicate that iMRI facilitates more aggressive yet safe resections, particularly in high-risk glioma cases. However, the implementation of iMRI in clinical practice requires careful consideration of training, resource allocation, and the potential variability in outcomes due to study design heterogeneity. Future research should focus on randomized controlled trials to better understand the cost-effectiveness and long-term benefits of iMRI, promoting its wider adoption in neurosurgical settings.

Surgical treatment of torticollis secondary to the presence of a congenital paracondylar process: illustrative case.

A paracondylar process is an abnormal bony exostosis arising from the skull base lateral to the occipital condyle and extending inferiorly toward the transverse process of the atlas. Paracondylar processes are typically identified incidentally and vary in size from a small protuberance to an elongated process. The authors present the first pediatric case of torticollis secondary to a congenital paracondylar process successfully treated with resection of the paracondylar process and sternocleidomastoid release. Cadaveric dissection, three-dimensional models, intraoperative imaging guidance, and multidisciplinary collaboration were paramount to a successful surgical outcome. https://thejns.org/doi/10.3171/CASE2447.

Intraoperative Image Guidance in Orbital and Lacrimal Surgery: A Report by the American Academy of Ophthalmology

To review the efficacy and safety of the use of intraoperative image guidance (IIG) in orbital and lacrimal surgery. A literature search of the PubMed database was last conducted in November 2023 for English-language original research that assessed the use of any image guidance system in orbital and lacrimal surgery that included at least 5 patients. The search identified 524 articles; 94 were selected for full-text analysis by the panel. A total of 32 studies met inclusion criteria. The panel methodologist assigned a level II rating to 2 studies and a level III rating to 30 studies. No study met the criteria for level I evidence. Procedures reported on were as follows: fracture repair (n= 14), neoplasm and infiltrate biopsy or excision (n= 6), orbital decompression for Graves ophthalmopathy (n= 3), dacryocystorhinostomy (n= 1), and mixed etiology and procedures (n= 8). Four studies used more than one IIG system. One study that met level II evidence criteria compared the outcomes of orbital fracture repair with IIG (n= 29) and without IIG (n= 29). Borderline better outcomes were reported in the IIG group: 2% versus 10% with diplopia (P= 0.039) and 3% versus 10% with enophthalmos (P= 0.065). The other level II study compared the repair of fractures with navigation (n= 20) and without (n= 20). The group in which navigation was used had a measured mean volume reduction of 3.82 cm3 compared with 3.33 cm3 (P= 0.02), and there was a greater measured reduction in enophthalmos in the navigation group of 0.72 mm (P= 0.001). Although the remaining 30 assessed articles failed to meet level II criteria, all alleged a benefit from IIG. No complications were reported. A small number of comparative studies suggest that there are improved outcomes when IIG is used in orbital fracture repair, but each study suffers from various limitations. No high-quality comparative studies exist for the management of lacrimal surgery, neoplastic disease, or decompression. Complications attributable to the use of IIG have not been identified, and IIG has not been analyzed for cost savings. Proprietary or commercial disclosure may be found after the references.

An Imaging-Compatible Oral Retractor System for Transoral Robotic Surgery.

This study aimed to develop and validate a Computed Tomography (CT)/Magnetic Resonance Imaging(MRI)-compatible polymer oral retractor system to enable intraoperative image guidance for transoral robotic surgery (TORS). The retractor was designed based on standard-of-care metallic retractors and 3D (three-dimensional) printed with carbon fiber composite and nylon. The system was comprehensively evaluated in bench-top and cadaveric experiments in terms of its ability to enable intraoperative CT/MR images during TORS, functionality including surgical exposure and working volume, usability, compatibility with da Vinci surgical systems, feasibility for disinfection or sterilization, and robustness over an extended period of time. The polymer retractor system enabled the acquisition of high-resolution and artifact-free intraoperative CT/MR images during TORS. With an inter-incisive distance of 42.55mm and a working volume of 200.09cm3, it provided surgical exposure comparable to standard-of-care metallic retractors. The system proved intuitive and compatible with da Vinci S, Xi, and Single Port systems, enabling successful mock surgical tasks performed by surgeons and residents. The retractor components could be effectively disinfected or sterilized for clinical use without significant compromise in material strength, with STERRAD considered the optimal method. Throughout a 2h mock procedure, the retractor system showed minimal displacements (<1.5mm) due to surrounding tissue deformation, with insignificant device deformation. The 3D-printed polymer retractor system successfully enabled artifact-free intraoperative CT/MR imaging in TORS for the first time and demonstrated feasibility for clinical use. This breakthrough opens the door to surgical navigation with intraoperative image guidance in TORS, offering the potential to significantly improve surgical outcomes and patients' quality of life.

Intraoperative image-guidance during robotic surgery: is there clinical evidence of enhanced patient outcomes?

To date, the benefit of image guidance during robot-assisted surgery (IGS) is an object of debate. The current study aims to address the quality of the contemporary body of literature concerning IGS in robotic surgery throughout different surgical specialties. A systematic review of all English-language articles on IGS, from January 2013 to March 2023, was conducted using PubMed, Cochrane library's Central, EMBASE, MEDLINE, and Scopus databases. Comparative studies that tested performance of IGS vs control were included for the quantitative synthesis, which addressed outcomes analyzed in at least three studies: operative time, length of stay, blood loss, surgical margins, complications, number of nodal retrievals, metastatic nodes, ischemia time, and renal function loss. Bias-corrected ratio of means (ROM) and bias-corrected odds ratio (OR) compared continuous and dichotomous variables, respectively. Subgroup analyses according to guidance type (i.e., 3D virtual reality vs ultrasound vs near-infrared fluoresce) were performed. Twenty-nine studies, based on 11 surgical procedures of three specialties (general surgery, gynecology, urology), were included in the quantitative synthesis. IGS was associated with 12% reduction in length of stay (ROM 0.88; p = 0.03) and 13% reduction in blood loss (ROM 0.87; p = 0.03) but did not affect operative time (ROM 1.00; p = 0.9), or complications (OR 0.93; p = 0.4). IGS was associated with an estimated 44% increase in mean number of removed nodes (ROM 1.44; p < 0.001), and a significantly higher rate of metastatic nodal disease (OR 1.82; p < 0.001), as well as a significantly lower rate of positive surgical margins (OR 0.62; p < 0.001). In nephron sparing surgery, IGS significantly decreased renal function loss (ROM 0.37; p = 0.002). Robot-assisted surgery benefits from image guidance, especially in terms of pathologic outcomes, namely higher detection of metastatic nodes and lower surgical margins. Moreover, IGS enhances renal function preservation and lowers surgical blood loss.

Fully automatic online geometric calibration for non-circular cone-beam CT orbits using fiducials with unknown placement.

Cone-beam CT (CBCT) with non-circular scanning orbits can improve image quality for 3D intraoperative image guidance. However, geometric calibration of such scans can be challenging. Existing methods typically require a prior image, specialized phantoms, presumed repeatable orbits, or long computation time. We propose a novel fully automatic online geometric calibration algorithm that does not require prior knowledge of fiducial configuration. The algorithm is fast, accurate, and can accommodate arbitrary scanning orbits and fiducial configurations. The algorithm uses an automatic initialization process to eliminate human intervention in fiducial localization and an iterative refinement process to ensure robustness and accuracy. We provide a detailed explanation and implementation of the proposed algorithm. Physical experiments on a lab test bench and a clinical robotic C-arm scanner were conducted to evaluate spatial resolution performance and robustness under realisticconstraints. Qualitative and quantitative results from the physical experiments demonstrate high accuracy, efficiency, and robustness of the proposed method. The spatial resolution performance matched that of our existing benchmark method, which used a 3D-2D registration-based geometric calibrationalgorithm. We have demonstrated an automatic online geometric calibration method that delivers high spatial resolution and robustness performance. This methodology enables arbitrary scan trajectories and should facilitate translation of such acquisition methods in a clinical setting.

A hyperspectral surgical microscope with super-resolution reconstruction for intraoperative image guidance.

Hyperspectral imaging (HSI) is an emerging imaging modality in medical applications, especially for intraoperative image guidance. A surgical microscope improves surgeons' visualization with fine details during surgery. The combination of HSI and surgical microscope can provide a powerful tool for surgical guidance. However, to acquire high-resolution hyperspectral images, the long integration time and large image file size can be a burden for intraoperative applications. Super-resolution reconstruction allows acquisition of low-resolution hyperspectral images and generates high-resolution HSI. In this work, we developed a hyperspectral surgical microscope and employed our unsupervised super-resolution neural network, which generated high-resolution hyperspectral images with fine textures and spectral characteristics of tissues. The proposed method can reduce the acquisition time and save storage space taken up by hyperspectral images without compromising image quality, which will facilitate the adaptation of hyperspectral imaging technology in intraoperative image guidance.

High-resolution intraoperative infrared thermography for the functional imaging and tumor resection maximization of a low-grade glioma: Technical case report

Currently, it is widely recognized the role of the extent of resection on overall and progression-free survival for gliomas surgery. Brain mapping and intraoperative image guidance are generally required to attain such an objective. Infrared Thermography (IRT) has a potential role in the identification of surgical margins, but it has not been consistently assessed in the literature. We aim to demonstrate the use of intraoperative IRT to detect superficial and deep tumoral margins of low-grade glioma, to identify adjacent functional motor cortex, and to maximize surgical resection in a 45-year-old lady with a long history of partial and secondary generalization seizures.

Dual-camera laparoscopic imaging with super-resolution reconstruction for intraoperative hyperspectral image guidance.

Laparoscopic and robotic surgery, as one type of minimally invasive surgery (MIS), has gained popularity due to the improved surgeon ergonomics, instrument precision, operative time, and postoperative recovery. Hyperspectral imaging (HSI) is an emerging medical imaging modality, which has proved useful for intraoperative image guidance. Snapshot hyperspectral cameras are ideal for intraoperative laparoscopic imaging because of their compact size and light weight, but low spatial resolution can be a limitation. In this work, we developed a dual-camera laparoscopic imaging system that consists of a high-resolution color camera and a snapshot hyperspectral camera, and we employed super-resolution reconstruction to fuse the images from both cameras to generate high-resolution hyperspectral images. The experimental results show that our method can significantly improve the resolution of hyperspectral images without compromising the image quality or spectral signatures. The proposed super-resolution reconstruction method is promising to promote the employment of high-speed hyperspectral imaging in laparoscopic surgery.

Advantages of an Image-Guided Subcranial Technique for Le Fort III Osteotomies for Midface Advancement: A Case Series

Objective: Le Fort III osteotomies are used to advance the midface in children with midface hypoplasia and syndromic craniosynostosis. Complications can occur during the subcranial osteotomies, leading todural violations as well as vascular and neurologic injuries. In patients with cerebrospinal fluid (CSF) shunts, CSF leak places them at risk of shunt infection. To avoid these injuries, surgeons may utilize an intracranial approach to gain optimal visualization of the cranial base for the horizontal cut through the ethmoid bone, at the naso-frontal junction, below the cribiform plate. A formal craniotomy to simply assure a safe osteotomy, however, may well be an unnecessary morbidity. The aim of this study was to describe the indications for and technical advantages of image guidance for subcranial Le Fort III osteotomies without a craniotomy. Methods: We describe the use of the StealthStation 3-D intraoperative image guidance system for subcranial Le Fort III osteotomies and associated clinical outcomes. An electronic medical record search at a single academic institution identified 10 patients with Current Procedural Terminology codes 21154-21155 (reconstruction midface, Le Fort III). Results: Six patients underwent image-guided subcranial Le Fort III osteotomies between 2008 and 2023. There were no cases of vascular injury, cranial nerve injury, or cerebrospinal fluid leak. No patients with a CSF shunt experienced shunt infection during follow up. Conclusions: Image-guidance provides technical advantages as an alternative approach to subcranial Le Fort III osteotomies while allowing the surgeon to avoid the morbidity of a craniotomy.

XIOSIS: An X-Ray-Based Intra-Operative Image-Guided Platform for Oncology Smart Material Delivery.

Image-guided interventional oncology procedures can greatly enhance the outcome of cancer treatment. As an enhancing procedure, oncology smart material delivery can increase cancer therapy's quality, effectiveness, and safety. However, the effectiveness of enhancing procedures highly depends on the accuracy of smart material placement procedures. Inaccurate placement of smart materials can lead to adverse side effects and health hazards. Image guidance can considerably improve the safety and robustness of smart material delivery. In this study, we developed a novel generative deep-learning platform that highly prioritizes clinical practicality and provides the most informative intra-operative feedback for image-guided smart material delivery. XIOSIS generates a patient-specific 3D volumetric computed tomography (CT) from three intraoperative radiographs (X-ray images) acquired by a mobile C-arm during the operation. As the first of its kind, XIOSIS (i) synthesizes the CT from small field-of-view radiographs;(ii) reconstructs the intra-operative spacer distribution; (iii) is robust; and (iv) is equipped with a novel soft-contrast cost function. To demonstrate the effectiveness of XIOSIS in providing intra-operative image guidance, we applied XIOSIS to the duodenal hydrogel spacer placement procedure. We evaluated XIOSIS performance in an image-guided virtual spacer placement and actual spacer placement in two cadaver specimens. XIOSIS showed a clinically acceptable performance, reconstructed the 3D intra-operative hydrogel spacer distribution with an average structural similarity of 0.88 and Dice coefficient of 0.63 and with less than 1 cm difference in spacer location relative to the spinal cord.

Rational design of NIR-II molecule-engineered nanoplatform for preoperative downstaging and imaging-guided surgery of orthotopic hepatic tumor

Orthotopic advanced hepatic tumor resection without precise location and preoperative downstaging may cause clinical postoperative recurrence and metastasis. Early accurate monitoring and tumor size reduction based on the multifunctional diagnostic-therapeutic integration platform could improve real-time imaging-guided resection efficacy. Here, a Near-Infrared II/Photoacoustic Imaging/Magnetic Resonance Imaging (NIR-II/PAI/MRI) organic nanoplatform IRFEP-FA-DOTA-Gd (IFDG) is developed for integrated diagnosis and treatment of orthotopic hepatic tumor. The IFDG is designed rationally based on the core “S-D-A-D-S” NIR-II probe IRFEP modified with folic acid (FA) for active tumor targeting and Gd-DOTA agent for MR imaging. The IFDG exhibits several advantages, including efficient tumor tissue accumulation, good tumor margin imaging effect, and excellent photothermal conversion effect. Therefore, the IFDG could realize accurate long-term monitoring and photothermal therapy non-invasively of the hepatic tumor to reduce its size. Next, the complete resection of the hepatic tumor in situ lesions could be realized by the intraoperative real-time NIR-II imaging guidance. Notably, the preoperative downstaging strategy is confirmed to lower the postoperative recurrence rate of the liver cancer patients under middle and advanced stage effectively with fewer side effects. Overall, the designed nanoplatform demonstrates great potential as a diagnostic-therapeutic integration platform for precise imaging-guided surgical navigation of orthotopic hepatic tumors with a low recurrence rate after surgery, providing a paradigm for diagnosing and treating the advanced tumors in the future clinical translation application.Graphical

MRI-based navigated cryosurgery of extra-abdominal desmoid tumors using skin fiducial markers: a case series of 15 cases

BackgroundPrecision surgery is becoming increasingly important in the field of Orthopaedic Oncology. Image-guided percutaneous cryosurgery (CRA) has emerged as a valid treatment modality for extra-abdominal desmoid tumors (EDTs). To date, most CRA procedures use CT-based guidance which fails to properly characterize tumor segments. Computer-guided MRI navigation can address this issue however, the lack of a fixed landmark for registration remains a challenge. Successful CRA correlates directly with precision approaches facilitated by intraoperative imaging guidance. This is the first study that attempts to assess the feasibility and efficacy of a novel approach of using skin fiducial markers to overcome the challenge of a MRI-based navigation CRA for symptomatic or progressive EDTs.MethodsIn this retrospective study conducted between 2018 and 2020, 11 patients at a single center with symptomatic or progressive EDTs were treated with CRA using intraoperative MRI navigation. Fifteen cryosurgery procedures were performed, each adhering to a personalized pre-operative plan. Total tumor size, viable and non-viable portions pre- and post-operation, and SF-36 questionnaire evaluating subjective health were recorded.ResultsAll CRAs demonstrated 100% adherence to the predetermined plan. Overall, tumor size decreased Median= -56.9% [-25.6, -72.4]) with a reduction in viable tissue, (Median= -80.4% [-53.3, -95.2]). Four patients required additional CRAs. Only one patient’s tumor did not reduce in size. One patient suffered from local muscle necrosis. Pre-operation, the average physical and mental scores 41.6 [29.4, 43] and 26.3 [17.6, 40.9] respectively. Post-operation, the average physical and mental scores were 53.4[38, 59.7] and 38 [31.2, 52.7] respectively.ConclusionThese findings provide an early indication of the feasibility and efficacy of performing percutaneous cryosurgery using skin fiducial marker registration for MRI-computed navigation to treat EDTs safely. Larger cohorts and multicenter evaluations are needed to determine the efficacy of this technique.

Endoscopic Transpterygoid Corridor for Petroclival Tumors: Case Series and Technical Nuances.

The petroclival area is a technically challenging region to operate owing to the proximity of the internal carotid artery (ICA) and the need to obtain gross total excision of tumors in this area as they are often resistant to radiotherapy. We present our experience with the endonasal endoscopic transpterygoid approach in managing tumors of the petroclival region and discuss various operative nuances for safer resection. A retrospective study of all consecutive cases of lesions occupying the petroclival region that were operated via endonasal endoscopic transpterygoid approach at our center between January 2016 and December 2021 was performed. The study included 14 cases of lesions occupying the petroclival region. Gross total resection by intraoperative observation was achieved in 10 patients, near total decompression was performed in two patients, and the remaining two patients underwent marsupialization of lesion. Postoperatively, one patient had right Lower motor neuron (LMN) facial nerve palsy and one patient required surgery for Cerebrospinal fluid (CSF) rhinorrhea on postoperative day 8. The mean duration of follow-up was 13.8 ± 16.6 months (range: 2-59 months). Four of six patients with visual symptoms on presentation reported improvement in vision, and the other two patients had a stable vision on follow-up. Two patients received radiotherapy postsurgery. No mortality was noted. The extended endonasal endoscopic transpterygoid approach can be safely and efficiently used for petroclival lesions. Very sound knowledge of anatomical relationship, use of intraoperative image guidance to avoid injury to ICA, and multilayer reconstruction with a vascularized nasoseptal flap are required to optimize the clinical outcome.