Surgical Visualization Research Articles

Computer-Assisted Navigation for Real Time Planning of Pedicle Subtraction Osteotomy in Cervico-Thoracic Deformity Correction.

Pedicle subtraction osteotomy (PSO) at the cervicothoracic junction (CTJ) is a powerful technique to correct severe kyphosis and sagittal malalignment. Reported techniques have demonstrated the safety and efficacy of the PSO, however limited visualization of surrounding tissues increases the potential for complications with this advanced technique. To describe the application of computed tomographic (CT)-based image guidance to the planning and execution of PSO at the CTJ. Intraoperative registration and verification of anatomic landmarks are performed with the intraoperative O-arm CT across the CTJ. With the navigation probe, the targeted pedicle is identified and the intended trajectories are rehearsed and saved on the navigational computer. As the PSO is performed, the navigation probe is used to check the depth, accuracy, and trajectory through each side. The extent of soft tissue dissection around the lateral aspect of the vertebral body through which the PSO is performed is also verified in real time. This technique was performed in 12 consecutive patients from 2013-2016. An IRB approved, retrospective analysis was performed from a prospective spinal deformity outcomes database. Patient consent is not required for publication as this report does not describe a specific case but rather a surgical technique used in practice. There were no vascular, esophageal, or soft tissue injuries in 12 consecutive patients. There were no cases of paralysis. Two patients developed hand weakness days after surgery. Intraoperative O-arm CT performed after closure of the osteotomy confirmed the accuracy of the osteotomy planning with no breach of the anterior cortical wall of the osteotomized vertebral body. CT-guided navigation allows for 3-dimensional visualization of the CTJ and minimizes complications associated with inadequate surgical visualization of vascular and deep organ structures.

The Surgical Approach Visualization and Navigation (SAVN) System reduces radiation dosage and surgical trauma due to accurate intraoperative guidance

ObjectThe intraoperative fluoroscopy has been widely used in modern neuro-spinal surgery due to the overwhelming trend toward minimal-access surgery. However, both patients and surgical personnel were under ionizing-radiation exposure during fluoroscopy usage. Since the fluoroscopy constitutes the vast majority of radiation exposure for both surgeons and patients, the development and improvement of new interventional possibilities are of great importance and interests. Patients and methodsA total of 20 patients were included in the current study, who received thoracic-spinal tumor resection via posterior midline approach. In comparison to the conventional C-Arm mobile fluoroscopy machine, the Surgical Approach Visualization and Navigation (SAVN) System was used to evaluate the effectiveness in reducing radiation. ResultsThe pain intensity and Japanese Orthopedic Association Score were equally ameliorated in patients of two groups. However, compared to C-arm group, the SAVN significantly reduced the screening time from 26.8 + 12.4 to 17.1 + 9.2 s (36.2% radiation reduction, P < 0.05), which was mainly due to the significant reduction of radiation attempts (from 12.8 + 4.9 to 7.1 + 5.5 times, P < 0.05). For patients, the direct and scatter radiation dose dropped 30.4% (P < 0.05) in the surgical region and 47.6% (P < 0.01) in the non-surgical region by using the SAVN System. Additionally, the tumor diameter/skin incision ratio increased from 0.39 + 0.4 to 0.47+ 0.28 after SAVN usage. Meanwhile, thedosimeter showed that the radiation dose to the primary surgeon was also lower in the SAVN group (72.1% reduction, P < 0.01). ConclusionComparing the conventional C-arm, the SAVN System based thoracic-spinal surgery significantly lowered radiation duration and dosage application towards both surgeons and patients.

Interactive Flying Frustums (IFFs): spatially aware surgical data visualization.

As the trend toward minimally invasive and percutaneous interventions continues, the importance of appropriate surgical data visualization becomes more evident. Ineffective interventional data display techniques that yield poor ergonomics that hinder hand-eye coordination, and therefore promote frustration which can compromise on-task performance up to adverse outcome. A very common example of ineffective visualization is monitors attached to the base of mobile C-arm X-ray systems. We present a spatially and imaging geometry-aware paradigm for visualization of fluoroscopic images using Interactive Flying Frustums (IFFs) in a mixed reality environment. We exploit the fact that the C-arm imaging geometry can be modeled as a pinhole camera giving rise to an 11-degree-of-freedom view frustum on which the X-ray image can be translated while remaining valid. Visualizing IFFs to the surgeon in an augmented reality environment intuitively unites the virtual 2D X-ray image plane and the real 3D patient anatomy. To achieve this visualization, the surgeon and C-arm are tracked relative to the same coordinate frame using image-based localization and mapping, with the augmented reality environment being delivered to the surgeon via a state-of-the-art optical see-through head-mounted display. The root-mean-squared error of C-arm source tracking after hand-eye calibration was determined as [Formula: see text] and [Formula: see text] in rotation and translation, respectively. Finally, we demonstrated the application of spatially aware data visualization for internal fixation of pelvic fractures and percutaneous vertebroplasty. Our spatially aware approach to transmission image visualization effectively unites patient anatomy with X-ray images by enabling spatial image manipulation that abides image formation. Our proof-of-principle findings indicate potential applications for surgical tasks that mostly rely on orientational information such as placing the acetabular component in total hip arthroplasty, making us confident that the proposed augmented reality concept can pave the way for improving surgical performance and visuo-motor coordination in fluoroscopy-guided surgery.

Postoperative Venous Thromboembolism after Extracranial Otologic Surgery.

To determine the incidence of postoperative venous thromboembolism (VTE) in adults undergoing otologic surgery. Cross-sectional retrospective study. Single tertiary academic center. Adults undergoing nononcologic, extracranial otologic surgery from August 2009 to December 2016. Patients with postoperative diagnosis VTE codes were identified. Imaging and clinical documents were searched for VTE evidence within the first 30 postoperative days. Methods of thromboprophylaxis were documented, and Caprini risk scores were calculated. In total, 1213 otologic surgeries were evaluated. No postoperative VTE events were identified (0/1268). Mean age was 51.0 ± 17.3 years (range, 18.1-93.4 years). Average length of surgery was 136.0 ± 79.0 minutes (range, 5-768 minutes). The average Caprini score in all patients was 4.0 ± 1.7 (range, 1-15). Eighty-five percent of patients had a Caprini score ≥3, the threshold at which chemoprophylaxis has been recommended in general surgery patients by the American College of Chest Physicians 2012 guidelines. Six patients had documented preoperative chemoprophylaxis and a Caprini score of 4.8 ± 1.7. This was not significantly different from that of patients who did not receive preoperative chemoprophylaxis (t test, P = .3). The literature would estimate a rate of 3.7% VTE in adults with similar Caprini scores undergoing general surgery procedures with no VTE prophylaxis. The Caprini risk assessment model may overestimate VTE risk in patients undergoing extracranial otologic surgery. Postoperative VTE following otologic surgery is rare, even in patients traditionally considered moderate or high risk. Chemoprophylaxis guidelines in this group should be balanced against the potential risk of increased intraoperative bleeding and its associated effects on surgical visualization and morbidity.

Surgical Aid Visualization System for Glioblastoma Tumor Identification based on Deep Learning and In-Vivo Hyperspectral Images of Human Patients.

Brain cancer surgery has the goal of performing an accurate resection of the tumor and preserving as much as possible the quality of life of the patient. There is a clinical need to develop non-invasive techniques that can provide reliable assistance for tumor resection in real-time during surgical procedures. Hyperspectral imaging (HSI) arises as a new, noninvasive and non-ionizing technique that can assist neurosurgeons during this difficult task. In this paper, we explore the use of deep learning (DL) techniques for processing hyperspectral (HS) images of in-vivo human brain tissue. We developed a surgical aid visualization system capable of offering guidance to the operating surgeon to achieve a successful and accurate tumor resection. The employed HS database is composed of 26 in-vivo hypercubes from 16 different human patients, among which 258,810 labelled pixels were used for evaluation. The proposed DL methods achieve an overall accuracy of 95% and 85% for binary and multiclass classifications, respectively. The proposed visualization system is able to generate a classification map that is formed by the combination of the DL map and an unsupervised clustering via a majority voting algorithm. This map can be adjusted by the operating surgeon to find the suitable configuration for the current situation during the surgical procedure.

A practical marker-less image registration method for augmented reality oral and maxillofacial surgery.

Image registration lies in the core of augmented reality (AR), which aligns the virtual scene with the reality. In AR surgical navigation, the performance of image registration is vital to the surgical outcome. This paper presents a practical marker-less image registration method for AR-guided oral and maxillofacial surgery where a virtual scene is generated and mixed with reality to guide surgical operation or provide surgical outcome visualization in the manner of video see-through overlay. An intraoral 3D scanner is employed to acquire the patient's teeth shape model intraoperatively. The shape model is then registered with a custom-made stereo camera system using a novel 3D stereo matching algorithm and with the patient's CT-derived 3D model using an iterative closest point scheme, respectively. By leveraging the intraoral 3D scanner, the CT space and the stereo camera space are associated so that surrounding anatomical models and virtual implants could be overlaid on the camera's view to achieve AR surgical navigation. Jaw phantom experiments were performed to evaluate the target registration error of the overlay, which yielded an average error of less than 0.50mm with the time cost less than 0.5s. Volunteer trial was also conducted to show the clinical feasibility. The proposed registration method does not rely on any external fiducial markers attached to the patient. It performs automatically so as to maintain a correct AR scene, overcoming the misalignment difficulty caused by patient's movement. Therefore, it is noninvasive and practical in oral and maxillofacial surgery.

Preclinical Safety Evaluation of Ophthalmic Viscosurgical Devices in Rabbits and a Novel Mini-Pig Model.

IntroductionTo establish the preclinical safety and equivalency of ophthalmic viscosurgical devices (OVDs) comprised of bacterially sourced sodium hyaluronate (HA) to animal sourced HA using pyrogenicity and aqueous exchange models in rabbits and a novel mini-pig model to evaluate corneal endothelial cell protection in vivo.MethodsHEALON OVD and HEALON5 OVD containing animal-derived HA and HEALON PRO OVD and HEALON5 PRO OVD containing bacterial-derived HA were used. Two rabbit aqueous exchange studies were conducted where aqueous humor was exchanged with OVDs in six animals each to observe potential ocular inflammation, intraocular pressure (IOP) response, corneal health and pachymetry until 7 days post procedure, as well as overall assessment of the OVDs. Endothelial cell protection was evaluated in a Yucatan mini-pig cataract surgery model where HEALON PRO and HEALON5 PRO OVDs were compared to HEALON and HEALON5 OVDs, respectively. Following cataract surgery with use of OVDs in six animals per study, animals were evaluated for ocular and general health, IOP, corneal thickness, ocular inflammation, and endothelial cell protection on days 1, 3, 7 and 14 post-surgery.ResultsAll rabbit studies demonstrated equivalence between bacterial-derived and animal-derived OVDs. Mild, post-surgical irritation, IOP increase, and corneal thickness measurements were not significantly different in HEALON PRO OVD and HEALON5 PRO OVD compared to HEALON and HEALON5 OVDs, respectively. The mini-pig model developed to investigate endothelial cell protection was successful in demonstrating equivalence between the OVDs studied. Changes in IOP mirrored actual surgical procedures, while corneal pachymetry and endothelial cell density remained constant for all OVDs used. Slit lamp observations showed expected inflammation following surgical procedures, likely due to challenges encountered during surgical procedures.ConclusionRabbit pyrogenicity and aqueous exchanged paired with a novel simulated cataract surgery mini-pig model demonstrate equivalence of OVDs regardless of HA source. Albeit with challenges, the mini-pig model was shown to be a promising tool for endothelial cell evaluation during the development of new OVDs for ophthalmic use.FundingJohnson & Johnson Surgical Vision, Inc.

GPS Laparoscopic Ultrasound: Embedding an Electromagnetic Sensor in a Laparoscopic Ultrasound Transducer

Tracking the location and orientation of a laparoscopic ultrasound (LUS) transducer is a prerequisite in many surgical visualization and navigation applications. Electromagnetic (EM) tracking is a preferred method to track an LUS transducer with an articulating imaging tip. The conventional approach to integrating EM tracking with LUS is to attach an EM sensor on the outer surface of the imaging tip (external setup), which is not ideal for routine clinical use. In this work, we embedded an EM sensor inside a standard LUS transducer. We found that ultrasound image quality and the four-way articulation function of the transducer were not affected by this sensor integration. Furthermore, we found that the tracking accuracy of our integrated transducer was comparable to that of the external setup. An animal study conducted using the developed transducer suggests that an internally embedded EM sensor is a clinically more viable approach, and may be the future of tracking an articulating LUS transducer.

The Effectiveness of Intravenous Tranexamic Acid on Blood Loss and Surgical Time During Endoscopic Sinus Surgery: A Systematic Review

Objective: To review the effectiveness of intravenous tranexamic acid in reduction of blood loss, surgical time and field visualization among patients who underwent endoscopic sinus surgery (ESS) for chronic rhinosinusitis (CRS). &#x0D; Methods:&#x0D; Data Sources: MEDLINE (PubMed), EMBASE, ScienceDirect, HERDIN, and the Cochrane Library.&#x0D; Eligibility Criteria: Randomized controlled trials (RCT) between 2005-2014 that evaluated the effects of tranexamic acid or placebo in patients undergoing ESS for CRS.&#x0D; Appraisal and Synthesis Methods: Articles were selected by 2 independent reviewers and methodological quality was blindly evaluated using a Jadad scale. Data were compiled in tables for analysis of outcome measures (estimated blood loss, length of surgery and intraoperative surgical field visualization).&#x0D; Results: Two trials were included in the study, enrolling 128 patients. One arm of the study had been given tranexamic acid while the other arm was given placebo (saline solution). Results varied for both studies. The summary of the observed difference for blood loss had a standardized mean difference of -51.20 (CI95 [-59.44, -42.95]) showing that the blood loss in milliliters was less in the tranexamic group compared to saline solution. The summary of the observed difference in surgical time had a standardized mean difference of -19.32 (CI95 [-24.21, -14.43]) showing that the surgical time in minutes was shorter in the tranexamic group compared to saline solution. The secondary outcome on surgical field visualization was not pooled together because the studies used different measurement scales.&#x0D; Limitations: The most important weaknesses of the 2 included studies were the differences in dose of tranexamic acid, scales of measurement of field visibility and age groups of the patients. &#x0D; Conclusion: Tranexamic acid reduced blood loss and shortened surgical time after ESS among patients with CRS. However, the additional benefit of tranexamic acid for better field visualization was not clear. Adverse effects were not considered in this study, however results support the use of intravenous tranexamic acid intraoperatively as an option for ESS with blood loss as a concern. Further randomized clinical trials and an update on the systematic review will strengthen the evidence on the effectivity of tranexamic acid for ESS.&#x0D; Keywords: tranexamic acid, endoscopic sinus surgery, bleeding time

Comparison of a Three-Dimensional Heads-Up Display Surgical Platform with a Standard Operating Microscope for Macular Surgery

To assess safety, efficacy, and outcomes of vitreoretinal surgery for macular pathology using a 3-dimensional heads-up display (3D HUD) surgical platform compared with a standard operating microscope (SOM). Prospective, single-center, unmasked, randomized study. Patients undergoing pars plana vitrectomy (PPV) for epiretinal membrane (ERM) or full-thickness macular hole (MH) at Wills Eye Hospital. Patients were randomized 1:1 to undergo surgery with a 3D HUD surgical platform or SOM. Patients who had previous PPV were excluded. Surgical choices, including PPV gauge, were based on surgeon preference. Standard surgical safety parameters, Early Treatment Diabetic Retinopathy Study visual acuity (VA), minimum required endoillumination levels, operative times, and surgeon "ease of use" of the viewing platform were recorded. Patients were followed up to postoperative month 3 (POM3). The main outcome measures were total operative time, macular peel time, surgeon rating of viewing system ease of use, minimum required endoillumination, intraoperative complication rate, and postoperative VA. Thirty-nine eyes of 39 patients with a mean age of 67.60±8.21 SD years were enrolled. Indications included ERM (n = 26 [3D HUD = 14, SOM = 12]) and MH (n = 13 [3D HUD = 9, SOM = 4]). Minimum required endoillumination was significantly lower with 3D HUD (mean 22.70%±15.10% SD) compared with SOM (mean 39.06%±2.72%; P < 0.001). There was no significant difference in overall operative time, but macular peel time was significantly longer using 3D HUD (mean 14.76±4.79 minutes) than SOM (11.87±8.07 minutes; P= 0.004). Surgeon-reported ease of use was significantly higher (easier) using SOM compared with 3D HUD (P= 0.004). There was no statistically significant difference between the groups in POM3 logarithm of the minimum angle of resolution (logMAR) VA or change in logMAR VA from baseline (all P > 0.681). There were no clinically significant intraoperative complications in either group. Three-dimensional heads-up display surgical visualization is an evolving technology demonstrating comparable efficacy to the SOM for macular surgery. Although overall surgical times were similar, 3D HUD macular peel times were longer and associated with less ease of use in this study, which may partly be due to a learning curve with new technology.

Comparing the Effect of Oral Clonidine and Tranexamic Acid on Bleeding and Surgical Field Quality during Functional Endoscopic Sinus Surgery

Bleeding during functional endoscopic sinus surgery (FESS) is an important issue for both anesthesiologists and surgeons as it can affect the safety and efficiency of the procedure. We compared the efficacy of tranexamic acid (TXA) and clonidine in reducing blood loss and improving surgical field visualization during FESS. In a double-blind, randomized, clinical trial, 52 patients, American Society of Anesthesiologists (ASA) physical status 1-2, aged 13-75 years, suffering from rhinosinusitis with or without polyposis, and who were candidates for FESS, were enrolled. The first group received intravenous TXA 15 mg/kg diluted in 100 ml normal saline, administered during 10-min infusion after induction. In the second group, 0.2 mg oral clonidine was given 1 to 1.5 hours before surgery. Duration of surgery, hemoglobin level, heart rate, blood pressure, and quality of surgical field based on Boezzart's scale and surgeon satisfaction based on Likert's scale were recorded in both groups. In total, 52 patients, 27 (51.9%) males and 25 (48.07%) females were studied. Twenty-two (42.3%) and 30 (57.7%) were in the TXA and clonidine groups, respectively. The mean pre- and post-surgical hemoglobin level showed no meaningful difference between the two groups. The same result was obtained for blood pressure and heart rate at different time points (P>0.05). Mean anesthesia time (P=0.859), mean surgical time (P=0.880), surgeon's satisfaction of the surgical field (P=0.757) and surgical field quality at different time points revealed no significant difference between the two groups. Premedication with oral clonidine and intravenous TXA has the same effect on bleeding during FESS, surgical field visualization, and surgeon satisfaction.

THE INTEGRATIVE SURGICAL THEATER: Combining Intraoperative Optical Coherence Tomography and 3D Digital Visualization for Vitreoretinal Surgery in the DISCOVER Study.

To evaluate the feasibility of integrating intraoperative optical coherence tomography (OCT) with a digital visualization platform for vitreoretinal surgery. The DISCOVER study is a prospective study examining microscope-integrated intraoperative OCT across multiple prototypes and platforms. For this assessment, a microscope-integrated OCT platform was combined with a three-dimensional (3D) surgical visualization system to allow for digital display of the OCT data stream on the large immersive display. Intraoperative OCT scans were obtained at various surgical milestones that were directly overlaid to the surgical view in a 55-inch passive 3D 4K high-definition display. Surgeon feedback was obtained related to system performance and integration into the surgical procedures through a prespecified surgeon questionnaire. Seven eyes of seven subjects were identified. Clinical diagnosis included epiretinal membrane (n = 3), macular hole (2), symptomatic vitreous opacity (1), and proliferative vitreoretinopathy (1). Optical coherence tomography images were successfully obtained and displayed on the 4K screen in all cases. Intraoperative OCT images facilitated identification of subtle retinal alterations. Surgeons reported that the 4K screen seemed to provide improved visualization of the OCT data stream compared with the semitransparent ocular view. Surgeons were able to examine the OCT data on the 4K screen without reverting to the external display system of the microscope. The system provided a uniform surgical visualization experience for both the surgeon and the assistant. In addition, the digital platform allowed all surgical personnel to simultaneously view both the OCT and the surgical field. All eyes underwent uneventful vitrectomy without reverting to the conventional microscope. No intraoperative adverse events occurred. Integration of OCT into the digital visualization system may enable unique opportunities for surgeon feedback of intraoperative diagnostics. The overlay of the OCT data onto the 4K monitor seemed to provide excellent visualization of OCT details. Further research is needed to compare the conventional microscope-based approach to the digital 3D screen approach in regards to intraoperative OCT.

One-lung ventilation in a patient with a large mass on the glottis

Rationale:One-lung ventilation (OLV) is required during most thoracic surgeries to facilitate surgical visualization by collapsing the lung. Double-lumen tubes and bronchial blockers are two commonly used devices for OLV; however, it may be difficult to place two devices in patients with narrow inlets, such as those that have tumor-induced airway stenosis.Patient concerns:We report the case of an adult patient with a lung tumor that was growing rapidly and hemorrhaging; thus, a thoracotomy for lung resection should have been performed as early as possible. However, a large mass on the glottis obstructed the entry of the double-lumen tube or bronchial blocker. Therefore, the operation could not be performed because of the inability to provide one-lung ventilation via the conventional intubation method.Diagnoses:Computed tomography (CT) revealed a lung tumor that was growing rapidly and preoperative bronchoscopy showed a large mass on the vocal cords.Interventions:After anesthesia induction, a Uniblocker and a small single lumen tube were intubated and the Uniblocker was inserted extraluminally of the single lumen tube. One-lung ventilation was achieved successfully in this patient.Outcomes:The surgery proceeded uneventfully for 4 hours without any complications.Lessons:Extraluminal use of the Uniblocker and a small single lumen tube may be recommended for patients receiving OLV and who have narrow inlets, especially under emergency situations.

Endometriosis.

Endometriosis is a common inflammatory disease characterized by the presence of tissue outside the uterus that resembles endometrium, mainly on pelvic organs and tissues. It affects ~5-10% of women in their reproductive years - translating to 176 million women worldwide - and is associated with pelvic pain and infertility. Diagnosis is reliably established only through surgical visualization with histological verification, although ovarian endometrioma and deep nodular forms of disease can be detected through ultrasonography and MRI. Retrograde menstruation is regarded as an important origin of the endometrial deposits, but other factors are involved, including a favourable endocrine and metabolic environment, epithelial-mesenchymal transition and altered immunity and inflammatory responses in genetically susceptible women. Current treatments are dictated by the primary indication (infertility or pelvic pain) and are limited to surgery and hormonal treatments and analgesics with many adverse effects that rarely provide long-term relief. Endometriosis substantially affects the quality of life of women and their families and imposes costs on society similar to those of other chronic conditions such as type 2 diabetes mellitus, Crohn's disease and rheumatoid arthritis. Future research must focus on understanding the pathogenesis, identifying disease subtypes, developing non-invasive diagnostic methods and targeting non-hormonal treatments that are acceptable to women who wish to conceive.

Endoscopic Sinus Surgery Perioperative Outcome after Intravenous Tranexamic Acid:

Objectives: To determine the effect of a single intravenous dose of tranexamic acid on intraoperative bleeding, duration of surgery, and surgical field visualization during endoscopic sinus surgery.&#x0D; &#x0D; Methods:&#x0D; Study Design: Double-blind, randomized, placebo-controlled trial.&#x0D; Setting: Tertiary Government Hospital in Quezon City&#x0D; Participants: 10 patients aged 18-75 years old diagnosed with chronic rhinosinusitis with or without nasal polyposis and unresponsive to medical treatment, who underwent endoscopic sinus surgery from September 2016 to August 2017, were randomly allocated to treatment group and control group respectively. The “odd” numbers were assigned to the treatment group (intravenous Tranexamic acid) given 1 dose of 100mg/ml (500mg tranexamic acid per 5 ml) tranexamic acid slow intravenous drip 1 hour prior to the procedure, while the “even” numbers assigned to the control group received the same amount of normal saline solution.&#x0D; &#x0D; Results: The mean duration of surgery of the tranexamic group was 185 minutes (standard deviation, SD 55.23) and the control group was 122.6 minutes (SD 42.03) showing no significant difference (p=.08). The mean blood loss of the tranexamic group was less at 240ml (SD 108.39) compared with the control group at 290ml (SD 74.16), although there was no statistically significant difference (p=.42). Intraoperative surgical field assessed by the surgeon based on the Boezart grading scale showed that 2 (40%) of the tranexamic group had higher bleeding score compared with the placebo group. However, this was not found to be statistically significant (p=.460). Due to the small sample size, a type II error occurred with alpha level of 0.05 and estimated power of 0.0885, with not enough basis to refute that a single dose of intravenous tranexamic acid has no effect in improving surgical field visualization during endoscopic sinus surgery. No drug side effects were noted after administration until after surgery.&#x0D; &#x0D; Conclusion: Single dose intravenous tranexamic acid in functional endoscopic sinus surgery decreased mean intraoperative blood loss (but this was statistically insignificant), but its effect on surgical field visualization cannot totally be assessed due to small sample size. There was also no change in the observed duration of surgery. No untoward side effects associated were noted from administration of the drug until after the surgery finished.&#x0D; &#x0D; Keywords: Functional endoscopic sinus surgery, intravenous tranexamic acid, chronic rhinosinusitis

Pneumothorax: Laparoscopic Intraoperative Management During Fundoplication Facilitates Management of Cardiopulmonary Instability and Surgical Exposure.

Intraoperative pneumothorax may complicate surgery by obscuring surgical view and cause cardiorespiratory instability during fundoplication with large hiatus hernia. Proactive intraoperative treatment may reduce conversion and drain insertion and facilitate timely completion of surgery. The authors present effective surgical and anesthetic measures to alleviate pneumothorax, which are helpful for hemodynamic stability and surgical visibility. Pneumothorax can complicate surgery by reducing surgical vision and causing cardiorespiratory instability. There is no requirement for laparoscopic or intercostal drainage. The authors provide various techniques to control intraoperative pneumothorax.

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.

Robotic right colonic resection. Is the robotic third arm a game-changer?

Minimally invasive surgery (MIS) approaches have produces relevant advancements in the pre/intra/postoperative outcomes. The conventional laparoscopic approach presents similar oncological results in comparison to laparotomic approaches. Despite these evidences, a considerable part of the colorectal operations are still being performed in an open way. This is in part because traditional laparoscopy may have some hurdles and a long learning curve to reach mastery. The robotic technology may help in increasing the MIS penetrance in colorectal surgery. The use of the R3 can potentially increase the number of surgical options available. In this retrospective case series, after a long robotic colorectal experience connected to a robotic program started by Giulianotti et al. in October 2000, we present our results regarding a subset of colorectal patients who underwent robotic right colonic resections performed, all by a single surgeon (P.C.G.), using the R3 according to our standardized technique. Out of all the robotic colorectal operations performed, this sub-sample sample included 33 patients: 21 males and 12 females. The age range was between 51 and 95 years old. The Body Mass Index (BMI) was between 21.6 to 43.1. The conversion rate to laparoscopy or to open surgery has been 0%. No intraoperative complications have been registered. The postoperative complications rates are reported in this manuscript. The perfusion check of the anastomosis by Near-infrared ICG (Indocyanine Green) enhanced fluorescence has been used. In 11.2% of the sample, the site of the anastomosis has been changed after ICG-Test. Moreover, when the ICG perfusion test has been performed no leakage occurred. This subset of patients suggests the potential role of R3 and the benefits correlated to robotic surgery. In fact, the laparoscopic approach uses mostly a medial to lateral mobilization. Indeed, during laparoscopic surgery an early right colon mobilization may create problems in the surgical field visualization. In robotic surgery, R3 can lift upwards the cecum/ascending colon/hepatic flexure exposing, in doing so, the anatomical structures. Hence, we can use also the same approach of the open surgery (where the first step is usually the mobilization of the ascending colon mesentery). In other words, the R3 offers more operative options in terms of surgical pathways maintaining at the same time good perioperative outcomes. However, more studies are needed to confirm our findings.

Incidence of diplopia after division and reattachment of the inferior oblique muscle during orbital fracture repair

BackgroundWide surgical access to the orbital floor and medial wall is often impaired by the course of the inferior oblique muscle. There is no current consensus on the optimal surgical approach for exposure, and techniques involving inferior oblique division are generally shunned for concern of possible complications. ObjectiveTo determine the safety and outcomes of inferior oblique division and reattachment for surgical access to the orbital floor and medial wall during orbital fracture repair. MethodsRetrospective, single-center, review of 85 patients that underwent orbital floor, medial wall or combined fracture repair with division and reattachment of the inferior oblique near its origin. Measured characteristics include surgical approach, type of surgery, time to surgery, pre- and post-operative diplopia, enophthalmos, and complications. ResultsForty-five patients (52.9%) with no pre-operative diplopia were followed up for a mean of six months. Of these, six patients (13.3%) developed post-operative binocular diplopia that resolved in all patients on an average of three months (range 2–6 months). No patients developed torsional diplopia. One patient developed a hematoma two years later attributable to capsular contraction around the implant. ConclusionDivision and reattachment of the inferior oblique muscle is a safe method that allows for panoramic surgical visualization of the inferior and medial orbit.

A spatial registration method for navigation system combining O-arm with spinal surgery robot

The minimally invasive surgery in spinal surgery has become increasingly popular in recent years as it reduces the chances of complications during post-operation. However, the procedure of spinal surgery is complicated and the surgical vision of minimally invasive surgery is limited. In order to increase the quality of percutaneous pedicle screw placement, the O-arm that is a mobile intraoperative imaging system is used to assist surgery. The robot navigation system combined with O-arm is also increasing, with the extensive use of O-arm. One of the major problems in the surgical navigation system is to associate the patient space with the intra-operation image space. This study proposes a spatial registration method of spinal surgical robot navigation system, which uses the O-arm to scan a calibration phantom with metal calibration spheres. First, the metal artifacts were reduced in the CT slices and then the circles in the images based on the moments invariant could be identified. Further, the position of the calibration sphere in the image space was obtained. Moreover, the registration matrix is obtained based on the ICP algorithm. Finally, the position error is calculated to verify the feasibility and accuracy of the registration method.