Electrosurgical Systems Research Articles

Performance of the ENSEAL X1 Curved Jaw Tissue Sealer in thoracic procedures in a Japanese cohort: a case series report

BackgroundAdvanced vessel sealing electrosurgical systems have been widely adopted for grasping, cutting, and sealing vessels. Data remain sparse with regard to its use in thoracic procedures. Thus, a prospective case series, utilizing the ENSEAL X1 Curved Jaw Tissue Sealer (X1CJ) and its companion energy source, the Generator 11 (GEN11), in thoracic procedures was performed in a Japanese cohort.MethodsSubjects were recruited at two Japanese surgical sites. The primary endpoint of this post-market study was the achievement of hemostasis (≤ Grade 3) for each thoracic vessel transection. Performance endpoints included scores for tasks completed with X1CJ (adhesiolysis, lymphatics or tissue bundles divided, tissue grasping, tissue cutting, or tissue dissection); hemostasis grading vessel transected; additional products required to achieve hemostasis for Grade 4 vessel transections. Safety was evaluated by evaluating device-related adverse events. All endpoint data were summarized.ResultsForty subjects (50.0% female) of Asian ethnicity with a mean age of 67.6 ± 11.3 years underwent a lung resection. Estimated mean blood loss was 39.5 mL. Hemostasis was achieved in 97.5% of vessel transections. Thirty-seven vessel sealings resulted in a hemostatic Grade 1 (92.5%). All surgeons reported satisfaction/neutral in terms of tissue grasping (100.0%) while most reported satisfaction/neutral with tissue cutting (95.7%). One device-related serious adverse event was reported (2.5%), a chylothorax requiring an extension of hospitalization. There was no post-operative bleeding or deaths reported during the study period.ConclusionThe X1CJ demonstrated safe and effective performance without any reports of significant intra-operative or post-operative hemorrhage in thoracic vessel sealing.

Modularized Electrosurgical System With a Hybrid CPU-FPGA Chip for Real-Time Thermal Lesion Approximation

Electrosurgery that ablates the target tissues such as tumor and nerve cells using radio-frequency (RF) heating has been widely employed in the medical industry. Although the thermal lesion plays a key role in the efficacy and safety for this method, it is still difficult to identify the depth and size of the lesion during the treatment using recent electrosurgical systems. Herein, we propose a novel electrosurgical instrument for real-time approximation of thermal lesions during RF ablation (RFA). Thermal lesions were numerically calculated based on theoretical thermal models using a hybrid central processing unit (CPU)-field-programmable gate array (FPGA) chip. Other functions such as RF control, voltage, and temperature measurements were implemented using RF components in a modular manner. It can solve voltage distribution in 6 ms by repeating the calculation 5000 times and can anticipate the thermal lesion in 15.6 ms within a time step in real-time simulations. As a real-world validation, the feasibility of the system was demonstrated through an animal study using a swine model. The system is modularly designed using off-the-shelf chips and RF components to improve flexibility and scalability. It can be easily compatible with existing RF surgical applications and medical imaging devices and can improve the efficacy of RFA therapy.

Thermal effects of percutaneous application of plasma/radiofrequency energy on porcine dermis and fibroseptal network.

BackgroundSkin laxity is one of the defining characteristics of aging and can be the result of various factors including intrinsic aging, genetics, diet, stress, lifestyle, sun exposure, weight fluctuations, and smoking. Recent reports suggest the ability of subdermal energy application to reduce skin laxity. Thermal energy can be delivered using different devices including lasers, radiofrequency (RF) monopolar and bipolar devices, and plasma/RF devices. Plasma‐based energy platforms generate a plasma gas, allowing heat to be applied to the tissue. This study focused on the evaluation of thermal effect of plasma/RF compared to a monopolar RF device applied percutaneously to the subdermis and connective fibroseptal network in a porcine model.MethodsThe subdermal application of energy was conducted using a plasma/RF system and a monopolar RF system. Both low and high energy/temperature settings were evaluated in dynamic and stationary modes. Histomorphometry was used to determine the depth of thermal effect associated with each treatment setting.ResultsBoth dermis and fibroseptal network tissue exhibited the presence of microscopically thermally treated zones. There were no significant differences in average and maximum depths of thermal effect between the different handpieces and electrosurgical systems used for all treatment settings.ConclusionsNo significant differences in the thermal effect between plasma/RF and monopolar RF systems were observed, suggesting that plasma/RF systems can be safely used for the percutaneous application of energy in the subcutaneous space.

Risk assessment of neuromuscular stimulation by energy-based transurethral resection devices: an ex vivo test standard

BackgroundDuring transurethral resection of bladder tumours (TURB), radio-frequency (RF) currents can lead to adverse neuromuscular stimulation (NMS). Here we present a novel ex vivo method to determine the risk of RF generators and their bipolar TURB modes to cause NMS. We aimed to develop an experimental platform for safety evaluation of new RF generators and their modes with a newly established test standard, suitable for replacement or reduction of animal testing.MethodsWe tested four contemporary RF generators with their bipolar modes for TURB in saline. A two-stage ex vivo approach was pursued: First, we recorded voltages at possible positions of the obturator nerve behind a porcine bladder wall in a TURB model using 18 RF applications per generator. Second, these voltage records were used as stimuli to evoke nerve compound action potentials (CAPs) in isolated porcine axillary nerves. The NMS potential was defined as the ratio between the observed area under the CAPs and the theoretical CAP area at maximum response and a firing rate of 250 Hz, which would reliably induce tetanic muscle responses in most human subjects. The measurement protocol was tailored to optimise reproducibility of the obtained NMS potentials and longevity of the nerve specimens.ResultsAs prerequisite for the clinical translation of our results, the robustness of our test method and reproducibility of the NMS potential are demonstrated with an excellent correlation (r = 0.93) between two sets of identical stimuli (n = 72 each) obtained from 16 nerve segments with similar diameters (4.2 ± 0.37 mm) in the nerve model. The RF generators differed significantly (p < 0.0001) regarding NMS potential (medians: 0–3%).ConclusionsOur test method is suitable for quantifying the NMS potential of different electrosurgical systems ex vivo with high selectivity at a reasonable degree of standardization and with justifiable effort. Our results suggest that the clinical incidence of NMS is considerably influenced by the type of RF generator. Future generations of RF generators take advantage from the proposed test standard through higher safety and less animal testing. Health professionals and treated patients will benefit most from improved RF surgery using generators with a low NMS risk.

Surgical treatment of fibroids for subfertility.

Fibroids are the most common benign tumours of the female genital tract and are associated with numerous clinical problems including a possible negative impact on fertility. In women requesting preservation of fertility, fibroids can be surgically removed (myomectomy) by laparotomy, laparoscopically or hysteroscopically depending on the size, site and type of fibroid. Myomectomy is however a procedure that is not without risk and can result in serious complications. It is therefore essential to determine whether such a procedure can result in an improvement in fertility and, if so, to then determine the ideal surgical approach. To examine the effect of myomectomy on fertility outcomes and to compare different surgical approaches. We searched the Cochrane Gynaecology and Fertility Group (CGFG) Specialised Register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, Epistemonikos database, World Health Organization (WHO) International Clinical Trials Registry Platform search portal, Database of Abstracts of Reviews of Effects (DARE), LILACS, conference abstracts on the ISI Web of Knowledge, OpenSigle for grey literature from Europe, and reference list of relevant papers. The final search was in February 2019. Randomised controlled trials (RCTs) examining the effect of myomectomy compared to no intervention or where different surgical approaches are compared regarding the effect on fertility outcomes in a group of infertile women suffering from uterine fibroids. Data collection and analysis were conducted in accordance with the procedure suggested in the Cochrane Handbook for Systematic Reviews of Interventions. This review included four RCTs with 442 participants. The evidence was very low-quality with the main limitations being due to serious imprecision, inconsistency and indirectness. Myomectomy versus no intervention One study examined the effect of myomectomy compared to no intervention on reproductive outcomes. We are uncertain whether myomectomy improves clinical pregnancy rate for intramural (odds ratio (OR) 1.88, 95% confidence interval (CI) 0.57 to 6.14; 45 participants; one study; very low-quality evidence), submucous (OR 2.04, 95% CI 0.62 to 6.66; 52 participants; one study; very low-quality evidence), intramural/subserous (OR 2.00, 95% CI 0.40 to 10.09; 31 participants; one study; very low-quality evidence) or intramural/submucous fibroids (OR 3.24, 95% CI 0.72 to 14.57; 42 participants; one study; very low-quality evidence). Similarly, we are uncertain whether myomectomy reduces miscarriage rate for intramural fibroids (OR 1.33, 95% CI 0.26 to 6.78; 45 participants; one study; very low-quality evidence), submucous fibroids (OR 1.27, 95% CI 0.27 to 5.97; 52 participants; one study; very low-quality evidence), intramural/subserous fibroids (OR 0.80, 95% CI 0.10 to 6.54; 31 participants; one study; very low-quality evidence) or intramural/submucous fibroids (OR 2.00, 95% CI 0.32 to 12.33; 42 participants; one study; very low-quality evidence). This study did not report on live birth, preterm delivery, ongoing pregnancy or caesarean section rate. Laparoscopic myomectomy versus myomectomy by laparotomy or mini-laparotomy Two studies compared laparoscopic myomectomy to myomectomy at laparotomy or mini-laparotomy. We are uncertain whether laparoscopic myomectomy compared to laparotomy or mini-laparotomy improves live birth rate (OR 0.80, 95% CI 0.42 to 1.50; 177 participants; two studies; I2 = 0%; very low-quality evidence), preterm delivery rate (OR 0.70, 95% CI 0.11 to 4.29; participants = 177; two studies; I2 = 0%, very low-quality evidence), clinical pregnancy rate (OR 0.96, 95% CI 0.52 to 1.78; 177 participants; two studies; I2 = 0%, very low-quality evidence), ongoing pregnancy rate (OR 1.61, 95% CI 0.26 to 10.04; 115 participants; one study; very low-quality evidence), miscarriage rate (OR 1.25, 95% CI 0.40 to 3.89; participants = 177; two studies; I2 = 0%, very low-quality evidence), or caesarean section rate (OR 0.69, 95% CI 0.34 to 1.39; participants = 177; two studies; I2 = 21%, very low-quality evidence). Monopolar resectoscope versus bipolar resectoscope One study evaluated the use of two electrosurgical systems during hysteroscopic myomectomy. We are uncertain whether bipolar resectoscope use compared to monopolar resectoscope use improves live birth/ongoing pregnancy rate (OR 0.86, 95% CI 0.30 to 2.50; 68 participants; one study, very low-quality evidence), clinical pregnancy rate (OR 0.88, 95% CI 0.33 to 2.36; 68 participants; one study; very low-quality evidence), or miscarriage rate (OR 1.00, 95% CI 0.19 to 5.34; participants = 68; one study; very low-quality evidence). This study did not report on preterm delivery or caesarean section rate. There is limited evidence to determine the role of myomectomy for infertility in women with fibroids as only one trial compared myomectomy with no myomectomy. If the decision is made to have a myomectomy, the current evidence does not indicate a superior method (laparoscopy, laparotomy or different electrosurgical systems) to improve rates of live birth, preterm delivery, clinical pregnancy, ongoing pregnancy, miscarriage, or caesarean section. Furthermore, the existing evidence needs to be viewed with caution due to the small number of events, minimal number of studies and very low-quality evidence.

Plasmakinetic Vapoenucleation of the Prostate by Nesbit Technique

Introduction: Transurethral resection of the prostate (TURP) has been the gold standard in surgical management of patients with benign prostatic hyperplasia (BPH). The procedure has stood the test of time. The place of conventional TURP has come under scrutiny with emergence of bipolar electrosurgical systems that utilize normal saline for cutting. Plasmakinetic (bipolar) energy has demonstrated several advantages over conventional monopolar TURP. There has been an increasing trend favoring enucleation procedures using laser.1 The argument given is that they do more complete removal of prostatic adenoma up to the capsule. Recently, bipolar “enucleation” and “vapoenucleation” procedures have been proposed as advancements in the technology.2 We have tried to modify this technique of “vapoenucleation” by enucleating the lobes in a simple way using Nesbit's technique, which is simpler and easy to reproduce. We use the plasmakinetic button electrode for doing vaporization. Patients and Methods: The study was conducted at our center from January 2016 till June 2016 for a 6-month period and included 35 consecutive patients with obstructive lower urinary tract symptoms associated with BPH. Patients with moderate to severe enlargement (between >50 g and <100 g) of the prostate were included in the study. Any patients with renal failure, upper tract dilation, or secondary bladder stones were excluded from the study. Complete preoperative assessment with IPSS score, postvoid residual urine (PVRU) volume, and maximum flow rate (Qmax) were done in all cases. Patients' consent was obtained in all cases. The classical Nesbit approach was used for enucleation of the prostatic lobes. The equipment used was bipolar resectoscope (Olympus medical systems). An initial vaporization/resection was done at 12 o' clock position followed by vapoenucleation of right lateral lobe from 12 o' clock position till 7 o' clock position in anticlockwise manner. Similarly the procedure was repeated on the left side from 12 o' clock position till 5 o' clock position in clockwise manner. In the end, the lobes lying at the base devoid of most of the blood supply were resected quickly with a cutting loop. No morcellator was used for removal of prostatic tissue, thereby reducing procedure time. Finally, hemostasis is secured. Postoperative assessment was done at 3 months and included IPSS score, PVRU volume, and Qmax. Immediate postoperative outcomes such as catheter-free trial, blood loss, operative time, and hospital stay were recorded. Late complications during the 3 months follow-up were recorded. Results: Thirty-five patients underwent plasmakinetic vapoenucleation of the prostate (PKVEP). The mean prostate volume on preoperative ultrasonography was 65.7 cc and mean operative time was 55 minutes. Mean catheterization time was 37.6 hours, whereas mean hospital stay was 64 hours. The mean resected tissue weight was 32 g. There was a significant improvement from baseline in terms of IPSS, Qmax, and PVRU volume in all the patients. No significant complications were noted within the short follow-up of 3 months. Conclusions: Transurethral PKVEP is a safe and effective method in management of BPH. In our study, we found the learning curve to be more flat as it mimics the Nesbit's technique of monopolar TURP. No competing financial interests exist. Author(s) have received and archived patient consent for video recording/publication in advance of video recording of procedure. Runtime of video: 7 mins 12 secs Presented as video at the World Congress of Endourology 2016 held at Cape Town, South Africa on November 8–12, 2016.

Development of high frequency generator for bipolar electrosurgical unit

Power Electronics is widely used in bioscience and medical instruments such as Electrosurgical Units, MRI and X-ray. An advance development in switch mode power supply leads to a new design topology of DC to DC convertor for Electrosurgical Systems. The new designed system has a capacity to produce high efficient output power with high resonance, this improves the performance of the surgery operation. This paper reports a Buck-Boost topology DC to DC (Flyback) converter with high power switching. The simulation results show an improved performance when compared to the existing system.

Hysteroscopic Endometrial Polypectomy: Clinical and Economic Data in Decision Making

Study ObjectiveTo compare the costs of hysteroscopic polypectomy using mechanical and electrosurgical systems in the hospital operating room and an office-based setting. DesignRetrospective cohort study (Canadian Task Force classification II-2). SettingTertiary referral hospital and center for gynecologic care. PatientsSeven hundred and fifty-four women who underwent endometrial polypectomy between January 20, 2015, and April 27, 2016. InterventionsHysteroscopic endometrial polypectomy performed in the same-day hospital setting or office setting using one of the following: bipolar electrode, loop electrode, mechanical device, or hysteroscopic tissue removal system. Measurements and Main ResultsThe various costs associated with the 2 clinical settings at Palagi Hospital, Florence, Italy were compiled, and a direct cost comparison was made using an activity-based cost-management system. The costs for using reusable loop electrode resection-16 or loop electrode resection-26 were significantly less expensive than using disposable loop electrode resection-27, the tissue removal system, or bipolar electrode resection (p = .0002). Total hospital costs for polypectomy with all systems were significantly less expensive in an office setting compared with same-day surgery in the hospital setting (p = .0001). Office-based hysteroscopic tissue removal was associated with shorter operative time compared with the other procedures (p = .0002) ConclusionThe total cost of hysteroscopic polypectomy is markedly higher when using disposable equipment compared with reusable equipment, both in the hospital operating room and the office setting. Same-day hospital or office-based surgery with reusable loop electrode resection is the most cost-effective approach in each settings, but requires experienced surgeons. Finally, the shorter surgical time should be taken into consideration for patients undergoing vaginal polypectomy in the office setting, owing more to patient comfort than to cost savings.

Electrosurgery Induced Damage to Ti-6Al-4V and CoCrMo Alloy Surfaces in Orthopedic Implants In Vivo and In Vitro

BackgroundRecent observations of specific metal damage patterns on retrieved total joint implants implied a cellular origin and was termed inflammatory cell-induced (ICI) corrosion. Although ICI corrosion continues to present a potential damage source for metallic biomaterials surfaces, an alternate source of some damage patterns may arise from electrosurgery instruments in total joint arthroplasty. MethodsTo characterize electrosurgically-induced damage patterns on metal implants, a model system of highly polished CoCrMo and Ti-6Al-4V disks and commercial electrosurgical generator was evaluated in various modes and power settings using monopolar and bipolar configurations. Surfaces were tested dry, wet with phosphate-buffered saline, or covered with known thicknesses of hydrated 5% agarose hydrogel. ResultsIn all cases, surface damage was generated on both alloy surfaces, directly resulting from plasma discharge interacting with the metal. Direct surface contact caused pitting and oxide buildup at the contact area. Damage was produced through 3 mm thickness of hydrogel on the surface and across metal-metal junctions representing modular tapers. Damage patterns on wetted surfaces were highly consistent with damage patterns observed on retrieved total joint implants; circular, ruffled areas with centralized pits, occasionally presenting trail- and weld-like features. ConclusionSurgeons using electrosurgical systems in proximity to metallic implants should exercise caution. Discharge of electrical energy through implants can induce localized surface damage and may result in other adverse outcomes. Although these results show some damage reported to be ICI corrosion is indeed the result of electrosurgery, there remains damage observed in retrievals not explained by this process.

Hypertrophic scar of the conjunctiva presenting as an eyelid mass: an unusual complication after surgical treatment of a chalazion.

PurposeTo present a rare case of a conjunctival hypertrophic scar presenting as eyelid mass after surgical treatment of a chalazion.Case presentationA 74-year-old man visited our clinic with severe ocular discomfort and excessive lacrimation since several months in his left eye accompanied by itching of the upper eyelid. Examination of the anterior segment revealed a 6 mm (horizontal) × 8 mm (vertical) round, immobile, hard, mushroom-shaped protruding mass on the tarsal conjunctiva of his left eye. There was no associated pigmentation, ulceration, or tenderness. Excisional biopsy of the benign conjunctival tumor was performed using radiofrequency electrosurgical systems. The region of the excised conjunctiva was well-healed on postoperative day 14, and there was no recurrence until 1 year post-surgery. Histopathological examination demonstrated thick interlacing collagenous fibrous bundles oriented in random directions and fibroblastic proliferation. Immunohistochemical staining revealed that spindle-shaped fibroblasts were positive for CD34 and negative for smooth muscle actin. The excessive collagenous tissue was stained blue by Masson trichrome stain. These findings were consistent with a hypertrophic scar of the conjunctiva.ConclusionThis short report demonstrates that a hypertrophic scar of the conjunctiva can develop after surgery of a chalazion and cause severe ocular discomfort and excessive lacrimation. These lesions can be easily removed using simple excision.

A New Wave in Electrosurgery : A Review of Existing and Introduction to New Radio-Frequency and Microwave Therapeutic Systems

A review of experimentally and commercially available therapeutic systems that use radio-frequency (RF) and microwave energy is provided in the first part of this article. The second part considers new advanced electrosurgical systems that combine the advantages associated with the use of low-frequency RF energy and high-frequency microwave energy to enhance the overall clinical effect and discusses how the frequency of operation and the design of the antenna structure can be optimized to ensure the desired tissue effects are achieved. Consideration is also given to how the latest developments in high-frequency semiconductor power technology developed for the communications sector are enabling new microwave and millimeter-wave energy-based electrosurgical systems to be developed and commercialized at an affordable cost.

Simple technique for laparoscopic appendicectomy to ensure safe division of the mesoappendix

Different instruments, such as endoscopic stapler, endoscopic clip, monopolar hook cautery, harmonic scalpel, and vessel sealing instrument, have been described in appendiceal mesentery dissection (1). Cutting the appendiceal mesentery by laparoscopic scissors and suturing take more time and require intracorporeal experience to tie a knot. On the other hand, endoscopic stapler is expensive. Classical bipolar electrosurgical systems and ultrasonic thermal energy are inadequate for the hemostasis of vessels >2 mm in diameter (2). Several shortcomings are associated with the use of conventional monopolar diathermy, such as thermal injury risk, difficulty in hemostasis, smoke production, and the need of use of additional tools, such as bipolar graspers, sutures and clips. Sharp dissection has the advantage of high heat production with thermal spread in surrounding structures and charring. It has some risks of direct coupling to another metal instrument, direct sparking, and the passage of current from recently coagulated, electrically isolated tissue (3). A simple cost-effective technique is described in this article to provide safe division of the mesoappendix that avoids the use of diathermy with its potential hazards. The technique utilizes a small number of clips. It is particularly useful in cases where the cecum is mobile, as it saves the need for an additional port to achieve control at the base of the appendix. TECHNIQUE

Method for Detecting Ablation Damage Using Sensor Integration of Hot Biopsy Forceps

Method for Detecting Ablation Damage Using Sensor Integration of Hot Biopsy Forceps

Characterization of Plasma Parameters and Tissue Injury Produced by Plasma Electrosurgical Systems

Plasma and injury properties produced by US Medical Innovations (USMI) elec- trosurgical systems were characterized using an explant pig's liver samples. It was observed that plasma length, tissue temperature, and injury size increases with applied power increase. Transition from conventional to argon coagulation mode (<0.5 L/min) leads to redistribution of the discharge power over the larger tissue area causing abrupt decrease of injury depth and increase of eschar diameter. Flow rate is not a primary factor affecting the tissue temperature. The depth and diameter of injury was minimal for the case of hybrid argon plasma cut opera- tional mode.

The Role of Human Machine Interfaces in Industrial Development of Medical Devices

Electrosurgery is a widely used modality for separation of tissue plains, achievement of hemostasis and devitalization of pathologic tissue structures. Although this technology has been used in almost every operating room in the world for many many decades, it still is recognized by leading clinical organizations as potentially the most dangerous device during surgery (1). In addition to technical problems, human error is recognized to be an important factor in those unfavorable outcomes, especially as during medical procedures electrosurgical systems are in close proximity to the physician - patient interface and physically in direct contact with both.

A Methodology for Evaluating Electromagnetic Interference on Medical Equipment Used in Electrosurgical Procedures

Electromagnetic Interference (EMI) has been pinpointed as one of the causes of equipment malfunction and hazards occurring in electrosurgical procedures. Identification of source-victim relationships and parameter quantification of EMI comprise ways to minimize its undesirable effects. This work focuses on the conducted EMI found in electrosurgical systems, considering the patient's body as an electrical component of the system, using the model described by Standard IEC 479 and the impedance values published by Kanay, Chatterjee and Gandhi. In this case, patient burns and their causes were studied. Two kinds of ESUs and two different cardiac monitors, in compliance with IEC 601 standards were evaluated, comprising four systems and some configurations and conditions that present risks to the patient. Current signals flowing through an RA cardiac monitor cable were measured during four surgical procedures and compared with simulation results. Results did show full agreement between simulation and “in vivo” waveforms.

How to Use the Electro-Surgical Systems Safely? : From the Principle of the Electro Surgery to the Accidents Reduction

How to Use the Electro-Surgical Systems Safely? : From the Principle of the Electro Surgery to the Accidents Reduction