Sensorless Based Haptic Feedback Integration In Robot-assisted Pedicle Screw Insertion For Lumbar Spine Surgery: A preliminary cadaveric study.

Pedicle screw fixation is an essential surgical technique for addressing various spinal pathologies, including degenerative diseases, trauma, tumors, neoplasms, and infections. Despite its efficacy, the procedure poses significant challenges, notably the limited visibility of spinal anatomical landmarks and the consequent reliance on surgeon's hand-eye coordination. These challenges often result in inaccuracies and high radiation exposure due to the frequent use of fluoroscopy X-ray guidance. Addressing these concerns, this study introduces a novel approach to pedicle screw insertion by utilizing a robot-assisted system that incorporates sensorless based haptics incorporated 5-DOF surgical manipulation. This innovative system aims to minimize radiation exposure and reduce operating time while improving the surgeon's hand posture capabilities. The developed prototype, expected to be implemented using bilateral control, was tested through preliminary cadaveric experiments focused on the insertion of both percutaneous and open pedicle screws at the L4-L5 level of the lumbar spine. Validation of the Sensorless Haptic Feedback feature was an integral part of this study, aiming to enhance precision and safety. The results, confirmed by fluoroscopic x-ray images, demonstrated the successful placement of two percutaneous and two open pedicle screws, with average position and torque errors of 0.011 radians and 0.054 Nm for percutaneous screws, and 0.0116 radians and 0.0057 Nm for open screws, respectively. These findings underscore the potential of the sensorless haptic feedback in a robot-assisted pedicle screw insertion system to significantly reduce radiation exposure and improve surgical outcomes, marking a significant advancement in spinal surgery technology.

Design, proof-of-concept of single robotic hair transplant mechanisms for both harvest and implant of hair grafts.

The design and development of a prototype for a singular robotic hair transplant system capable of harvesting and implanting hair grafts were executed in this study. To establish a proof-of-concept for hair transplant procedures involving harvesting and implantation, a test system using a spherical phantom of the scalp was selected. The developed prototype of the robotic hair transplant system demonstrates the potential to reduce the duration that grafts remain without a blood supply, thereby minimizing hair graft damage. Additionally, the overall operation time for follicular unit extraction is comparatively shorter than that of conventional systems. Results from the robot vision tests indicate an 89.6% accuracy for hair graft detection with a 4 mm hair length phantom and 97.4% for a 2 mm hair length phantom. In the robot position control test, the root mean square error was found to be 1.268°, with a standard error of the mean of 0.203°. These outcomes suggest that the proposed system performs effectively under the conditions of a spherical phantom with a 2 mm hair length and a 5 mm distance between harvests.

Concurrent function of high-strength dry carbon fiber as resistive heating element and thermistor in ambient air.

Measuring temperature through carbon fiber reinforced plastics requires an implanted contact-based temperature sensor during resistive heating. Implanting the sensor brings about considerable complications in the heat-joining of soft biocompatible Carbon Fiber Reinforced Plastics (CFRPs). In this paper, the concurrent temperature-dependent Electrical Resistance (ER) behavior of Carbon Fiber (CF) tow along with resistive heating is introduced. The temperature feedback from CF tow was investigated in the range of 60-200 °C in the room condition. The process is characterized by high nonlinearity due to complex mode of heat loss, orthotropic and semi-conductive nature of CF, resistivity of contacts, gas-moisture adsorption and ambient changes. In such conditions, experiments were conducted to study the Current-Voltage (I-V), ER-time and ER-temperature in steady-state and transient modes. I-V relationship was non-ohmic and ER-temperature relationship showed negative temperature coefficient at temperatures above 60 °C. Exponential behavior similar to that of thermistors was identified in ER-temperature relationship. The relationship is expressed by Hoge-quartic model, 1 T = a + b ( ln R ( T ) ) + c ( ln R ( T ) ) 2 + d ( ln R ( T ) ) 3 + e ( ln R ( T ) ) 4 , showing the best fit among the conventional calibration equations of thermistor. The reversibility of ER-temperature relationship with maximum error of 16.4 °C was observed. The repeatability of the relationship shows the CF viability of providing concurrent temperature feedback during high-current Joule heating in the room condition.

Interactive 3D Force/Torque Parameter Acquisition and Correlation Identification during Primary Trocar Insertion in Laparoscopic Abdominal Surgery: 5 Cases.

Laparoscopic procedures have become indispensable in gastrointestinal surgery. As a minimally invasive process, it begins with primary trocar insertion. However, this step poses the threat of injuries to the gastrointestinal tract and blood vessels. As such, the comprehension of the insertion process is crucial to the development of robotic-assisted/automated surgeries. To sustain robotic development, this research aims to study the interactive force/torque (F/T) behavior between the trocar and the abdomen during the trocar insertion process. For force/torque (F/T) data acquisition, a trocar interfaced with a six-axis F/T sensor was used by surgeons for the insertion. The study was conducted during five abdominal hernia surgical cases in the Department of Surgery, Faculty of Medicine, Ramathibodi Hospital, Mahidol University. The real-time F/T data were further processed and analyzed. The fluctuation in the force/torque (F/T) parameter was significant, with peak force ranging from 16.83 N to 61.86 N and peak torque ranging from 0.552 Nm to 1.76 Nm. The force parameter was observed to positively correlate with procedural time, while torque was found to be negatively correlated. Although during the process a surgeon applied force and torque in multiple axes, for a robotic system, the push and turn motion in a single axis was observed to be sufficient. For minimal tissue damage in less procedural time, a system with low push force and high torque was observed to be advantageous. These understandings will eventually benefit the development of computer-assisted or robotics technology to improve the outcome of the primary trocar insertion procedure.

Surface coating of orthopedic implant to enhance the osseointegration and reduction of bacterial colonization: a review.

The use of orthopedic implants in surgical technology has fostered restoration of physiological functions. Along with successful treatment, orthopedic implants suffer from various complications and fail to offer functions correspondent to native physiology. The major problems include aseptic and septic loosening due to bone nonunion and implant site infection due to bacterial colonization. Crucial advances in material selection in the design and development of coating matrixes an opportunity for the prevention of implant failure. However, many coating materials are limited in in-vitro testing and few of them thrive in clinical tests. The rate of implant failure has surged with the increasing rates of revision surgery creating physical and sensitive discomfort as well as economic burdens. To overcome critical pathogenic activities several systematic coating techniques have been developed offering excellent results that combat infection and enhance bone integration. This review article includes some more common implant coating matrixes with excellent in vitro and in vivo results focusing on infection rates, causes, complications, coating materials, host immune responses and significant research gaps. This study provides a comprehensive overview of potential coating technology, with functional combination coatings which are focused on ultimate clinical practice with substantial improvement on in-vivo tests. This includes the development of rapidly growing hydrogel coating techniques with the potential to generate several accurate and precise coating procedures.

Ultrasound Triggered Drug Release from Affinity-Based ß-Cyclodextrin Polymers for Infection Control.

This work demonstrates a slow, sustained drug delivery system that provides on-demand delivery bursts through the application of pulsed therapeutic ultrasound (TUS). Insoluble ß-cyclodextrin-polymer (pCD) disks were loaded with a saturated antibiotic solution of rifampicin (RIF) and used for drug delivery studies. To obtain on-demand release from the implants, TUS was applied at an intensity of 1.8 W/cm2. The therapeutic efficacy of the combination treatment was assessed in bacterial culture via an in vitro Staphylococcus aureus bioluminescence assay. The results demonstrated that the application of pulsed TUS at 3 MHz and 1.8 W/cm2 to pCD implants leads to a significantly higher short-term burst in the drug release rate compared to samples not treated with TUS. The addition of TUS increased the drug release by 100% within 4 days. The pCD disk + RIF stimulated with TUS showed a comparatively higher bacterial eradication with CFU/mL of 4.277E+09, and 8.00E+08 at 1 and 24 h compared with control treated bacteria at 1.48E+10. Overall, these results suggest that the addition of pulsed TUS could be an effective technology to noninvasively expedite antibiotic release on demand at desired intervals.

Endonasal endoscopic transsphenoidal approach robot prototype: A cadaveric trial.

BACKGROUND: The Endonasal Endoscopic Transsphenoidal Surgery (EETS) is a minimally invasive procedure to approach and remove pituitary tumors and other sellar lesions. The process causes less pain, faster recovery, and provides further minimal invasive access in critical cases. However, a slight deviation of tools from the target area can be fatal to the patients. The aim of this study is to design and develop a prototype robot to demonstrate neurosurgical robot-assisted EET approach. METHODS: The effectiveness of a prototype robot in executing a minimally invasive EET surgery was studied in 6 cadavers. The robot was associated with a multi-information integrated technique for surgery including QR code tracking. The robot was controlled and driven by the neurosurgeon. RESULTS: The standard procedure of EET was followed and the robot carried out the first stage of EET under the supervision of neurosurgeon. Finally, the sellar was reached by the neurosurgeon. The result was determined by qualitative analysis and was confirmed by the neurosurgeon. The time for the entire EET surgical procedure showed marked reduction compared to the traditional EET approach. CONCLUSION: The robot design was found to be technically feasible and hence can be used for assisting the EET procedure. The robot used was able to assist the neurosurgeon correctly to approach the sinus.

Anatomical Workspace Study of Endonasal Endoscopic Transsphenoidal Approach.

PURPOSE: To determine the workspace through an anatomical dimensional study of the skull base to further facilitate the design of the robot for endonasal endoscopic transsphenoidal (EET) surgery. METHODS: There were 120 cases having a paranasal sinus CT scan in the database. The internal volumes of the nasal cavities (NC), the volumes of the sphenoid sinuses (SS), and the distance between the anterior nasal spine and base of the sellar (d-ANS-BS) were measured. RESULTS: The Pearson correlation coefficient (PCC) between the relevant distances and the volumes of the right NC was 0.32; between the relevant distances and the volumes of the left NC was 0.43; and between the relevant distances and volumes of NC was 0.41; with a statistically significant difference (p < 0.001). All PCCs had a statistically significant meaningful difference (p < 0.05). CONCLUSION: The volume of NCs were significantly correlated with distances (p < 0.05). The safest and shortest distance to guide the robotic arm length in the EET approach could be represented by d-ANS-BS. This result was also used as primary information for further robotic design.

A Novel Design of N-Fiducial Phantom for Automatic Ultrasound Calibration.

BACKGROUND: Freehand ultrasound (US) is a technique used to acquire three-dimensional (3D) US images using a tracked 2D US probe. Calibrating the probe with a proper calibration phantom improves the precision of the technique and allows several applications in computer-assisted surgery. N-fiducial phantom is widely used due to the robustness of precise fabrication and convenience of use. In principle, the design supports single-frame calibration by providing at least three noncollinear points in 3D space at once. Due to this requirement, most designs contain multiple N-fiducials in unpatterned and noncollinear arrangements. The unpatterned multiple N-fiducials appearing as scattered dots in the US image are difficult to extract, and the extracted data are usually contaminated with noise. In practice, the extraction mostly relied on manual interventions, and calibration with N-fiducial phantom has not yet achieved high accuracy with single or few frame calibrations due to noise contamination. AIMS: In this article, we propose a novel design of the N-fiducial US calibration phantom to enable automatic feature extraction with comparable accuracy to multiple frame calibration. MATERIALS AND METHODS: Along with the design, the Random Sample Consensus (RANSAC) algorithm was used for feature extraction with both 2D and 3D models estimation. The RANSAC feature extraction algorithm was equipped with a closed-form calibration method to achieve automatic calibration. RESULTS: The accuracy, precision, and shape reconstruction errors of the calibration acquired from the experiment were significantly matched with the previous literature reports. CONCLUSIONS: The results showed that our proposed method has a high efficiency to perform automatic feature extraction compared to conventional extraction performed by humans.

On the feasibility of a liquid crystal polymer pressure sensor for intracranial pressure measurement.

Intracranial pressure (ICP) monitoring is crucial in determining the appropriate treatment in traumatic brain injury. Minimally invasive approaches to monitor ICP are subject to ongoing research because they are expected to reduce infections and complications associated with conventional devices. This study aims to develop a wireless ICP monitoring device that is biocompatible, miniature and implantable. Liquid crystal polymer (LCP) was selected to be the main material for the device fabrication. This study considers the design, fabrication and testing of the sensing unit of the proposed wireless ICP monitoring device. A piezoresistive pressure sensor was designed to respond to 0-50 mm Hg applied pressure and fabricated on LCP by standard microelectromechanical systems (MEMS) procedures. The fabricated LCP pressure sensor was studied in a moist environment by means of a hydrostatic pressure test. The results showed a relative change in voltage and pressure from which the sensor's sensitivity was deduced. This was a proof-of-concept study and based on the results of this study, a number of recommendations for improving the considered sensor performance were made. The limitations are discussed, and future design modifications are proposed that should lead to a complete LCP package with an improved performance for wireless, minimally invasive ICP monitoring.

Analysis of Endonasal Endoscopic Transsphenoidal (EET) surgery pathway and workspace for path guiding robot design.

BACKGROUND: Endoscopic Endonasal Transsphenoidal Surgery (EETS) is the standard method to treat pituitary adenoma, tumor in the pituitary gland which would affect human beings in terms of hormonal malfunction and other symptoms. This procedure provides extra minimal invasive access in severe cases. The objective of this paper is to design and develop a prototype of EET robot with navigation guidance system based on the study of EET workspace and pathway to determine a safe space for surgical tool insertion. METHODS: The EET workspace and its pathway were studied via data collected from EET experiments on 70 cadavers. An optical tracking system was used to detect and record the movement of the surgical tools during the experiments. Delaunay triangulation and Voronoi diagram were utilized to determine the cloud position of the gathered data for EET workspace. Moreover, in order to determine the EET pathway voxelization methods were incorporated. RESULTS: The average diameter of the workspace calculated was 19.08 with 3.32 S. D, the average length and volume of the workspace were 53.9 mm and 15.9cm3, respectively. The S.D values determined for length and volume were 7.2 and 6.02, respectively. For the pathway, a high density area was determined via data obtained through cloud position. CONCLUSION: Dimension of the EET workspace and characters of EET pathway determine robot's requirements to design and develop EET robotic system. This article demonstrates the conceptual design of an EET robot and successfully accomplishes the goal of guidance and aids in assisting the EET procedures.

Breast biopsy navigation system with an assisted needle holder tool and 2D graphical user interface.

OBJECTIVE: This paper proposes the development of a breast biopsy navigation system with an assisted needle holder tool for a coaxial needle and a graphical user interface, which utilizes an optical tracking device to localize the needle position relative to the ultrasound image with the aim to improve performance especially for a new radiologist or an inexperienced group. MATERIALS AND METHODS: The system consists of an assisted needle holder tool, which as an attachment for the 2D ultrasound transducer and the graphical user interface (GUI) that shows the needle pathway, needle line and warning signs. An optical tracking system is used to track the needle motion, ultrasound image and transform all information to with respect to the technique. The system is evaluated using a phantom made from gel candle. There were nine experienced and eight inexperienced participants who performed the breast biopsy intervention, using three methods: the freehand method, only the needle holder tool guidance, and the whole navigation guidance (GUI + assisted needle holder). RESULTS: The results demonstrate a success rate of over 90% using only assisted needle holder and the whole system to perform breast biopsy for the experienced and inexperienced groups, whereas for the inexperienced group a success rate of 57.5% was achieved using the freehand method. The use of only assisted needle holder for breast biopsy reduces the time for a procedure in the inexperienced group by 6 s when compared to the freehand method. CONCLUSION: The authors believe that this navigation system can be applied in a clinical setting and give an advantage to inexperienced radiologists who must successfully perform clinical breast biopsy.

A novel robotic monofilament test for diabetic neuropathy.

OBJECTIVE: The use of the Semmes-Weinstein (SW) monofilament test is recommended as a screening method for diabetic neuropathy. It offers an important chance to prevent further complications of diabetic foot. We aimed to develop a prototype Robotic Monofilament Inspector that can be used as a standard machine for screening of diabetic neuropathy. METHODS: Development was divided into three parts: computer software, control box, and Robotic Monofilament Inspector. The examiner conducted the SW test (by hand and by robotic inspector), vibration perception threshold, and Toronto Clinical Scoring System without knowledge of patient information. The unpaired t test or Wilcoxon rank-sum test was used to determine the differences between independent groups in terms of continuous outcomes, while the χ(2) test was used to determine categorical outcomes. Agreement between the various diabetic neuropathy tests was measured using the kappa statistic. RESULTS: The SW test and vibration perception threshold were more valid tests for neuropathy than the Toronto test. The robotic test was in excellent agreement with the two former tests and appeared to be valid (kappa statistic, 0.35-0.81). Another indirect evidence for the validity of the robotic test was the finding that diabetic patients with foot ulcers had a higher prevalence of neuropathy (77%vs. 38%). This might indicate that the robotic test was more valid than the manual test. CONCLUSION: The Robotic Monofilament Inspector could be used as a simple screening machine. This prototype may be developed further for routine clinical use.

Three-dimensional aortic aneurysm model and endovascular repair: an educational tool for surgical trainees.

OBJECTIVES: Endovascular aortic aneurysm repair (EVAR) is a current valid treatment option for patients with abdominal aortic aneurysms (AAAs). The success of EVAR depends on the selection of appropriate patients, which requires detailed knowledge of the patient's vascular anatomy and preoperative planning. Three-dimensional (3D) models of AAA using a rapid prototyping technique were developed to help surgical trainees learn how to plan for EVAR more effectively. METHOD: Four cases of AAA were used as prototypes for the models. Nine questions associated with preoperative planning for EVAR were developed by a group of experts in the field of endovascular surgery. Forty-three postgraduate trainees in general surgery participated in the present study. The participants were randomly assigned into two groups. The 'intervention' group was provided with the rapid prototyping AAA models along with 3D computed tomography (CT) corresponding to the cases of the test, while the control group was provided with 3D CTs only. RESULTS: Differences in the scores between the groups were tested using the unpaired t test. The mean test scores were consistently and significantly higher in the 3D CT group with models compared with the 3D CT group without models for all four cases. Age, year of training, sex and previous EVAR experience had no effect on the scores. CONCLUSION: The 3D aortic aneurysm model constructed using the rapid prototype technique may significantly improve the ability of trainees to properly plan for EVAR.