Monopolar Technique Research Articles

Robot-Assisted Hysterectomy Using the Double-Bipolar Method

ObjectiveTo demonstrate the efficacy of the double-bipolar method in a benign hysterectomy. DesignStepwise demonstration of the technique with a narrative video. SettingThe double-bipolar method was first reported in 2011 [1] and is gaining popularity in Japan; however, its usefulness in robot-assisted hysterectomy is under-reported. When unexpected bleeding occurs during robot-assisted hysterectomy using a monopolar technique, corrective measures may be prolonged and often require changing forceps. The Maryland forceps have 4 functions, including incision, dissection, grasping, and coagulation, which enable rapid responses to bleeding and reduce forceps changes and cost. Previously, we reported the usefulness of the double-bipolar technique in other surgical procedures [2,3]. Herein, we present a case of robot-assisted hysterectomy using this technique at an urban general hospital, including detailed insights into its execution. InterventionsA 45-year-old female patient presented to our hospital with painful menstrual bleeding. Magnetic resonance imaging revealed an 8-cm myoma in the posterior wall of the uterine cervix. Consequently, a robot-assisted hysterectomy was performed using right-handed Maryland forceps (Intuitive, Sunnyvale, CA) and the ForceTriadTM Energy Platform (Medtronic, Minneapolis, MN) in the macro mode, with an output of 60 W. This configuration ensured a consistent electronic output, regardless of the electrical resistivity of the target tissues, facilitating precise incisions using a momentary high voltage [4]. The surgical duration was 60 minutes, and the estimated blood loss was 5 mL. ConclusionThe highly versatile double-bipolar method uses one forceps for incision, dissection, coagulation, and grasping and is useful in gynecological surgery. Video Abstract [Display omitted]

Comparison of holmium laser, bipolar and conventional monopolar transurethral resection of bladder tumour in primary non-muscle invasive bladder cancer.

To compare the efficiency and safety profile of conventional monopolar, bipolar plasmakinetic and holmium laser techniques for transurethral resection of bladder tumour. The prospective comparative study was conducted from July 2019 to May 2021 after approval from the ethicsreview committee of Kafrelsheikh University, Egypt, and comprised patients of either gender with primary non muscle invasive bladder cancer who qualified for transurethral resection of bladder tumour. The patients were stratified into low-risk group A, intermediate risk group B and high-risk group C in accordance with the guidelines of the European Association of Urology. Comprehensive cystoscopy and panendoscopy were done in all cases. Once panendoscopy was done, tumour resection was performed with monopolar resectoscope in group A, plasmakinetic resectoscope in group B and holmium laser in group C). Data was collected at preoperative, peroperative, postoperative and follow-up stages. Data was analysed using SPSS 21. Of the 84 patients, 67(79.76%) were males and 17(20.23%) were females. There were 27(32.14%) patients in group A; 21(77.8%) males and 6(22.2%) females withy mean age 60.63±11.76 years. Group B had 32(38%) patients; 26(81.2%) males and 6(18.8%) females with mean age 65.34±7.55 years. Group C had 25(29.76%) patients; 20(80%) males and 5(20%) females with mean age 59.48±12.6 years. The mean follow-up period was 12.97±2.70 months in group A, 12.81±2.75 monthsin group B and 13.48±3.3 monthsin group C. Visualised complete resection was done in 23(85.8%) group A patients, 29(90.6%) group B patients and 24(96%) group C patients(p=0.018). Visualised complete resection, tumour multiplicity, tumour size, catheter duration, and hospital stay were significant predictors (p<0.05). Survival analysis showed 26(96.3%), 30(93.75%) and 25(100%) cases in groups A, B and C, respectively. Bipolar plasmakinetic and holmium laser techniques were found to be more effective and safer than the conventional monopolar technique for transurethral resection of bladder tumour in patients with primary non-muscle invasive bladder cancer.

A prospective, randomized, single-blind study comparing coblation and monopolar extracapsular tonsillectomy.

ObjectiveThe aim of this study was to compare intraoperative blood loss, postoperative pain, post‐tonsillectomy hemorrhage (PTH), and medical costs associated with extracapsular tonsillectomy between coblation and monopolar electrocautery in children.Materials and methodsThis study included 293 patients aged 6–15 years planned to undergo extracapsular tonsillectomy. Data on estimated blood loss, postoperative pain score, operation time, PTH, and the cost of disposable equipment were collected.ResultsCoblation extracapsular tonsillectomy was associated with significantly lower mean pain scores than monopolar technique on postoperative days 1 (p <.001) and 2 (p = 0.02). However, the pain score was similar between the groups at all other time points. The monopolar group had a significantly shorter operation time compared to the coblation group (11.09 ± 7.53 vs. 17.12 ± 4.29 min, p <.001). Intraoperative estimated blood loss was not significantly different between the groups (p = .43).The cost of extracapsular tonsillectomy was significantly lower in the monopolar compared to the coblation group (US$ 28.18 vs. US$ 430.48, p <.001). PTH occurred in 17 patients (5.80%) and required a second surgery. Secondary PTH occurred in 6.16% (9/146) and 0.68% (1/147) of patients in the coblation and monopolar groups, respectively (p <.001). The PTH was significantly higher in the tonsillitis compared to in the tonsillar hypertrophy (12.37% vs. 2.55%, p = .002), However, the difference of PTH was not significant among mean pain scores subgroups. Of the 17 patients with PTH, the lower pole, middle portion, and upper pole were involved in 15 (88.24%), 2 (11.76%), and 0 cases, respectively.ConclusionsCoblation and novel monopolar electrocautery extracapsular tonsillectomy are associated with similar postoperative pain scores except on postoperative days 1 and 2. However, monopolar technique offers significant advantages over coblation method with less operative time, decreased secondary PTH, and cost.Level of Evidence: NA.

Percutaneous Endoluminal Radiofrequency Ablation of Occluded Biliary Metal Stent in Malignancy Using Monopolar Technique: A Feasibility Study.

To prove feasibility and safety of percutaneous endoluminal radiofrequency ablation (eRFA) using a monopolar approach in treatment of occluded biliary stent in malignancy. The study included 11 patients with occluded biliary metal stent that had been implanted due to malignant biliary obstruction. All underwent metal stent recanalization by percutaneous eRFA in monopolar setting. Sixteen eRFA procedures were performed under fluoroscopic guidance with an EndoHPB 8F radiofrequency ablation catheter. The effect of stent recanalization was assessed based upon change from pre- to post-procedural diameter of the patent lumen of the metal stent (Wilcoxon test), primary and secondary stent patency (compared by log-rank test), catheter-free period, and overall survival. Adverse events were evaluated according to Common Terminology Criteria for Adverse Events (CTCEA) 4.0. Recanalization of the metal stent by monopolar radiofrequency ablation was successful in all 11 patients. Diameter of the patent lumen of the stent significantly widened after the eRFA inside the stent (median 2 vs. 7mm, p = 0.003). Grade 1 complications were observed in one-third of procedures. Median stent patency after recanalization by eRFA was non-inferior to primary metal stent patency (154 vs. 161days, p = 0.27). Median catheter-free survival and overall survival after stent recanalization were 149 and 210days, respectively. Endoluminal radiofrequency ablation in monopolar setting was shown to be a feasible and safe method for recanalization of occluded biliary metal stents. Level 4, Case Series.

Comparison of Post-Tonsillectomy Hemorrhage between Monopolar and Plasma Blade Techniques.

The plasma blade is an innovative device that was recently introduced for performing tonsillectomy. While one of the benefits of the plasma blade is limited thermal damage, the effects of plasma blades on postoperative hemorrhage have not been thoroughly investigated. Patients who underwent tonsillectomy in our institution between January 2013 and September 2018 were retrospectively enrolled in the study. A total of 1214 patients were enrolled in the study, with 759 participants who underwent monopolar tonsillectomy and 455 participants who underwent plasma blade tonsillectomy. In total, 14 bleeding events occurred in the monopolar group, and 10 events occurred in the plasma blade group. The odds ratio for postoperative bleeding in the plasma blade group was 1.20 (95% CI 0.52 to 2.72). After adjusting for potential confounders, the adjusted odds ratio was 1.34 (95% CI 0.58 to 3.07). In conclusion, there is no significant difference in post-tonsillectomy hemorrhage rates between the traditional monopolar technique and plasma blade technique. Plasma blade tonsillectomy can be considered as safe as traditional monopolar tonsillectomy.

Monopolar tonsillotomy versus cold dissection tonsillectomy in children: Prospective study on postoperative recovery

ObjectivesTo compare postoperative self-reported recovery results with monopolar tonsillotomy and cold dissection tonsillectomy in children. To evaluate the feasibility of the monopolar technique in tonsillotomy. MethodsChildren <12 years undergoing tonsillotomy or tonsillectomy between April 2018 and March 2020 who (with a caregiver) were willing to participate in a two-week follow-up formed the study group. They filled in a questionnaire about pain-related outcomes, return to normal activities, weight changes, complications, and length of home care. ResultsAltogether 166 patients were recruited; 103 (62%) returned the questionnaire. The first pain-free day with tonsillotomy was day 5 and with tonsillectomy day 11. After tonsillotomy, patients returned to normal activities faster, e.g. they were able to eat normally 6.5 days earlier than tonsillectomy patients. During the first postoperative week weight dropped after tonsillectomy, but not after tonsillotomy. The length of home care was 6 days with tonsillotomy and 10 days with tonsillectomy. The incidence of postoperative hemorrhage (including minor bleedings at home) was 14% after tonsillotomy and 32% after tonsillectomy. Hemorrhages needing interventions were 0% with tonsillotomy and 2% with tonsillectomy. ConclusionChildren operated on with monopolar tonsillotomy recovered faster and had less postoperative hemorrhage than those undergoing tonsillectomy. They were able to return earlier to daycare/school and their caregivers back to work. Recovery results with monopolar tonsillotomy were equal to other tonsillotomy techniques reported in the literature, hence the monopolar technique can be considered an alternative method to perform tonsillotomy.

Algorithm for management of patients of the period of menopausal transition with recurrence of anomalous uterine bleeding associated with beneficial proliferative changes of endometry

Aim. To compile an algorithm for managing patients during the menopausal transition with a relapse of abnormal uterine bleeding associated with benign proliferative changes in the endometrium and evaluate its outcomes.&#x0D; Materials and methods. The observation of 150 patients aged 4555 years who had recurrence of abnormal uterine bleeding due to benign proliferative changes of the endometrium. All patients underwent hysteroresectoscopic ablation of the endometrium according to the monopolar coagulation-vaporization technique using Olympus equipment (Japan). The patients were divided into two groups. One group was formed by 98 women who, before hysteroscopic ablation of the endometrium, received hormonal preparations for 14 months, with the help of which suppressive changes in the uterine mucosa up to 34 mm were achieved. The other group consisted of 52 patients of the menopausal transition who did not receive preoperative drug therapy, and the thinning of the endometrium before hysterectomy was performed instrumentally. After hysteroresectoscopy, the period of clinical and instrumental observation was 2 years.&#x0D; Results. Based on the results of the study, an algorithm has been compiled for the treatment of women during the menopausal transition with abnormal uterine bleeding, including at the first stage a clinical, laboratory and instrumental examination with the selection of a group of patients to be treated by endometrial ablation, and at the second stage, measures for the preoperative thinning of the uterine mucosa, at the third stage performing hysteroresectoscopic ablation of the endometrium; and at the fourth stage dynamic monitoring during ie 2 years. The preoperatively achieved medical atrophy of the endometrium, followed by hysteroresectoscopy, contributes to an improvement of 20.3% in the results of treatment of patients in comparison with mechanical thinning of the endometrium before hysteroresectoscopy. In general, the developed algorithm increases the effectiveness of anti-relapse treatment to 92.8%.&#x0D; Conclusion. In practical health care, the proposed algorithm should be used, including successive steps. Following the algorithm, a differentiated approach to the choice of therapeutic tactics is carried out, taking into account not only morphological changes in the endometrium, but also the associated gynecological and somatic pathology of the patient, as well as justifying the conduct of preoperative preparation for hysteroresectoscopic ablation of the endometrium and determining the order of subsequent dynamic observation.

Bipolar radiofrequency ablation of mandibular branch for refractory V3 trigeminal neuralgia.

Background: Percutaneous trans-foramen ovale (FO) radiofrequency ablation (RFA) of Gasserian ganglion (GG) is commonly used to treat V3 trigeminal neuralgia (TN). However, this intracranial approach is less selective and safe.Objectives: To report a novel percutaneous within-FO RFA of the V3 under CT-guidance and outcomes with both bipolar and monopolar techniques.Patients and methods: Twenty-six patients with isolated V3 primary TN and FO >6 mm in diameter underwent either monopolar (n=12) or bipolar RFAs (n=14) based on their preference. Successful analgesia over V3, residual pain, recurrent pain, and complications were compared between the two groups. The ex vivo egg albumen model was used to demonstrate the size difference in the thermocoagulation lesion created by monopolar vs bipolar electrodes.Results: In the bipolar group, there were more cases of masticatory atonia as compared to the monopolar (P=0.104), but no residual pain was observed. In the monopolar group, there were two cases of residual pain found, which led to immediate repeat RFAs. Therefore, during the immediate post-operative period, both groups obtained 100% complete V3 analgesia with a similar risk of facial hematoma (P=0.641). During up to 27-months of post-operative follow-up, in the bipolar group, complete pain relief persisted in all patients; in the monopolar group, 1 case of recurrent pain was found at 14 months. Ex vivo study demonstrated that, at 90 °C/90 seconds of RFA, the width of lesions is significantly larger by the 6-mm spacing parallel-tip bipolar electrodes compared to the monopolar electrode (9.5±0.567 vs 5.5±0.07 mm).Conclusion: In treating patients with isolated V3 TN and FO >6mm in diameter, this percutaneously within-FO RFA of the V3 under CT guidance is both clinically practical and effective, while bipolar RFA is associated with a lower incidence of residual and recurrent pain likely due to larger lesion sizes.

Establishing a porcine model of suture-free nonischemic partial nephrectomy by monopolar electrocoagulation

Objective To establish a porcine model of suture-free nonischemic partial nephrectomy by monopolar electrocoagulation technique, and observe the effect of this technique on postoperative residual kidney. Methods The study was conducted on six Guizhou local minipigs. The unilateral kidney was exposed with a surgical incision in parallel with the lumbosacral muscle. A partial nephrectomy (2 cm×2 cm×2 cm) was made in the middle pole without blocking the renal artery. The bleeding at the transaction surface was stopped not by traditional suturing but by electrocoagulation with a monopolar electric hook. The operation time and the renal bleeding volume were recorded. Three pigs were reared for 1 month after the surgery, and the urine color, coat color, and action responsiveness of the animals were monitored. Three pigs were sacrificed on day 7 after the surgery to observe thethe pathological changes at the surface of the partial nephrectomy. Results The operations of the 6 pigs were completed safely and successfully. The higher the power setting of monopolar electrocoagulation, the better the effect of the hemostasis. When the power reached 100 W, the electric hook was in the state of spray coagulation, and hemostasiswas completely achieved. The average operation time was 60 min (range, 30-90 min) and the average blood loss was about 42 ml (range, 30-60 ml). Three pigs were observed for 1 month after surgerywith no evidence of hematuria. They all hadshiny hair color and quick response with obvious sign of blood loss. On postoperative day 7, the kidneys were harvested from the other 3 pigs, and there was no perirenal hematoma or thrombosis in the kidney wound. HE staining identifiedcoagulation layer, necrotic layer and edema layer from the outer to inner of the wound. Conclusion Suture-free and nonischemic partial nephrectomy can be safely and reliablly established in minipigs using the monopolar electrocoagulation technique. Key words: Porcine; Partial nephrectomy; Nonischemia; Suturefree; Monopolar electrocoagulation

Clinical utility of multipolar ablation with a three-dimensional simulator system for patients with hepatocellular carcinoma

Purpose Recently, multipolar RFA has been utilized. Multipolar RFA offers the advantage of providing a large volume of ablation, providing more homogeneous necrosis with a higher rate of pathological complete necrosis. Although very encouraging results have been reported for multipolar RFA, the monopolar technique remains by far the most frequently used technique worldwide. We developed 3D sim-Navigator as a navigation and simulation system. For achieving insertion of electrodes around the tumor in a well-balanced manner, this system appeared very useful. To confirm the efficacy of multipolar ablation with new simulator system for patients with hepatocellular carcinoma by assessing for relapse-free survival and shape of the ablation volume under clinical conditions. Materials and Methods All participants provided written, informed consent, and study protocols were approved by the institutional ethics committee. Twenty-seven patients with 27 nodules were treated by no-touch ablation using the new simulator system. Another 21 patients with 21 nodules treated without the simulator system were enrolled as controls. Ablation was performed without inserting any applicator into the tumor by placing all electrodes around the tumor, if possible. Ablation was started after confirming a well-balanced positioning of electrodes around the tumor using the simulator system. In multipolar ablation, the positional relationships of multiple electrodes were easy to intuitively understand by repeated marking for insertions of the second and third RFA electrodes. The vertical cross-sectional image (C-plane) was utilized. Tumor progression and shape of ablation volume were assessed. Predictive factors of tumor progression were assessed by Cox proportional hazard model. Results No significant differences in clinical characteristics were seen between groups. Mean sphericity was 0.48 ± 0.07 with the 3D sim-Navigator and 0.37 ± 0.07 without the 3D sim-Navigator (P Conclusions Ideal ablation area was acquired by this simulation and navigation system in clinics. This system improved local tumor progression by appropriate insertion of multiple electrodes.

Вплив монополярного та біполярного методів резекції на відновні процеси в підшлунковій залозі

Мета. Порівняти особливості зміни тканин підшлункової залози після експериментальних хірургічних втручань, виконаних з використанням стандартної хірургічної техніки та біполярного і монополярного зварювання.&#x0D; Матеріали і методи. В умовах експерименту виконували резекцію підшлункової залози у білих лабораторних щурів з використанням стандартної хірургічної техніки, високоенергетичного електрохірургічного інструмента в біполярному режимі, високоенергетичного електрохірургічного інструмента в монополярному режимі. Гістологічні дослідження залози проводили безпосередньо після виконання операції та через 3, 7, 21 добу із застосуванням світлооптичного мікроскопа Leica DМ500.&#x0D; Результати. Після застосування стандартної хірургічної техніки в ранні терміни виникало більш виражене запалення та швидше наростав об’єм новоутвореної сполучної тканини, ніж після використання електрохірургічних методів у біполярному та монополярному режимах. Після обох видів електрорезекції в новоутвореній тканині на 7-му добу формувались протоки, чого не спостерігали після використання стандартної техніки. Після резекції, виконаної за допомогою монополярного зварювання, утворювався менш щільний коагуляційний прошарок, ніж після застосування біполярного методу. Через 21 добу в зоні резекції формувався більш значний об’єм сполучної тканини та зберігалися більш виражені ознаки запалення, ніж після використання біполярного методу.&#x0D; Висновки. У разі використання біполярної та монополярної техніки резекції скорочується тривалість виконання оперативного втручання, зменшується ризик виникнення кровотечі, утворюється більш герметичне з’єднання на резектованій поверхні, не ускладнюються процеси відновлення.

CLASSICAL MONOPOLAR RADIOFREQUENCY ABLATION IN TREATMENT OF LONG-Standing persistent Atrial FIBRILLATION: PROPENSITY SCORE MATCHING ANALYSIS

The article is devoted to the evaluation of the results of clinical application of penetrating radiofrequency ablation techniques on atrial myocardium.Material and Methods. A total of 298 patients with valvular heart disease complicated with atrial fibrillation were operated. All operations were performed under cardiopulmonary bypass and cardioplegia. The main group consisted of 198 patients who were operated using penetrating technique radiofrequency exposure. The control group consisted of 100 patients who underwent surgery with the use of «classical» monopolar radiofrequency-ablation technique. Both groups did not significantly differ in any parameter before surgery, but to increase confidence in the results, pseudo-randomization was performed using the Propensity score matching technique.Results. Patients with previous heart surgery were excluded during the selection of candidates for the procedure because of the presence of adhesions in the pericardium that did not allow good visualization of the left atrium, sufficient to perform the procedure. Penetrating technique had significantly higher efficiency compared to the «classic» technique in the early and long-term postoperative periods. The efficiency was 93% in the early postoperative period and 88% in the long term. The efficacy of «classical» monopolar procedure was lower: 86 and 68%, respectively.

Comparison of impact of monopolar versus bipolar resection of the prostate on erectile function in patients with benign hyperplasia of the prostate

Introduction and ObjectiveThe incidence of erectile dysfunction (ED) after TURP for BPH is still debated. Current study aims at comparing the impact of monopolar and bipolar TURP on the sexual function of male patients with LUTS, using the IIEF EF-domain score (questions 1–5, 15) and to identify statistical risk factors associated with development of post-operative ED. Patients and methodsBetween April 2014 and May 2015, 102 patients underwent TURP for symptomatic BPH. Sixty on underwent TURP by the monopolar technique and 41 by the bipolar technique. Patients were assessed on the day before the surgery by IIEF and followed up 3 and 6 months postoperatively, using the same scoring system. ResultsOn a 6 month follow up,13 patients (22.4%) in the monopolar group and 12 (30%) in the bipolar group, experienced clinical change in their EF score. Among risk factors studied, only diabetes, intraoperative capsular perforation and preoperative use of PDE5I had a statistically significant impact on the EF score.No statistically significant difference in IIEF score and EF domain score was observed between the patients who underwent TURP by the monopolar technique, compared to those patients in which the bipolar one was used; whether at three months (p value 0.33) or at six months (p value 0.397). ConclusionNo statistical difference could be detected between monopolar and bipolar TURP, regarding the risk of developing post-operative ED. However, a higher incidence of ED should be anticipated in patients with DM, intraoperative capsular perforation and preoperative use of PDE5I.

Monopolar vs. bipolar transurethral resection for non–muscle invasive bladder carcinoma: A post-hoc analysis from a randomized controlled trial

PurposeTraditionally, transurethral resection of bladder tumors (TURB) is performed using monopolar technique. Bipolar resection has been postulated to reduce complications. In this study we compare safety and efficacy between monopolar TURB (mTURB) and bipolar TURB (bTURB) for patients with primary non-muscle invasive bladder cancer (NMIBC). Materials and methodsData were obtained from an international multicenter randomized clinical trial that compared the use of white light cystoscopy with narrow band imaging-assisted TURB using the Olympus system between 2010 and 2014. Main outcomes of interest were operative time, perioperative, and postoperative complications, and 12-month recurrence-free survival. ResultsIn total, 716 patients were treated for primary NMIBC with mTURB (310 patients) or bTURB (406 patients). The use of white light cystoscopy or narrow band imaging was equally distributed between the 2 resection techniques. Multilevel logistic and linear regression corrected for possible confounders showed no significant difference between mTURB and bTURB for postoperative complications (OR = 1.76, P = 0.180), postoperative bleeding (OR = 1.27, P = 0.722), and the combination of intra + postoperative bleeding (OR = 1.992, P = 0.108). Additionally, no significant difference was found between mTURB and bTURB concerning operative time (1.05min. longer for bTURB, P = 0.536), intraoperative bleeding requiring intervention (OR:1.38, P=0.809), incidence of obturator reflex (OR = 0.93, P = 0.854), and bladder perforation (OR = 3.05, P = 0.195). In total, 185 patients (25.8%) developed a recurrence (mTURB = 88, bTURB = 97). Recurrence-free survival at 12 months in the mTURB and bTURB group was 70% and 74% (P = 0.410), respectively. ConclusionBased on these results, bTURB is as safe and effective as mTURB in treatment of primary NMIBC. bTURB seems to have no evident advantages over mTURB with respect to operation time, perioperative and postoperative complication rates, and recurrence rates at 12 months.

Anatomical Comparison of Radiofrequency Ablation Techniques for Sacroiliac Joint Pain

To compare the percentage of sacral lateral branches (LBs) that would be captured if lesions were created by seven current sacroiliac joint (SIJ) radiofrequency ablation (RFA) techniques: three monopolar and four bipolar. Cadaveric fluoroscopy study. Anatomy and surgical skills laboratories. Forty cadaveric SIJs. LBs were exposed, radiopaque wires were sutured to LBs, and anterior-posterior fluoroscopic images through the S1 superior endplate were obtained. Lesions that would be created by 17 versions of seven current SIJ RFA techniques were mapped on the fluoroscopic images. These 17 versions were compared: 1) percentage of LBs that would be captured; 2) percentage of SIJ specimens in which 100% of LBs would be captured; and 3) percentage of LBs that would not be captured at each level (S1-S4). Both the mean LB and 100% capture rates were greater for the bipolar techniques (93.4-99.7% and 62.5-97.5%, respectively) than for the monopolar techniques (49.6-99.1% and 2.5-92.5%, respectively) evaluated. For the bipolar techniques, 1.5-29.2% of LBs would not be captured at S1 and 0% at S2-S4 vs 0-29.2% at S1-S4 for the cooled monopolar techniques vs 36.9-100% at S1-S4 for the conventional monopolar technique. The findings suggest that, if lesions were created, the RFA needle placement locations of the bipolar techniques evaluated may be capable of capturing all LBs, but those of the current monopolar techniques evaluated may not. Future in vivo imaging studies are required to compare the lesion morphology generated by different SIJ RFA techniques and correlate the findings with clinical outcomes.

Role of Hydro-Dissection Facilitated Monopolar Cauterization Dissection Technique on Separation of the Greater Omentum From the Superior Layer of the Transverse Mesocolon During D2 Radical Gastrectomy

Adequate separation of the omentum from the transverse colon mesentery, during D2 radical gastrectomy, is usually difficult and often time-consuming due to anatomic variations. The aim of this prospective study was to compare the electrocautery dissection technique with hydrodissection-facilitated electrocauterization for the separation of the greater omentum from the superior layer of the transverse mesocolon in gastric cancer patients undergoing D2 radical gastrectomy. The time taken to separate the greater omentum from the superior layer of the transverse mesocolon, and the number and extension of iatrogenically-created mesocolonic defects were assessed. Forty patients were prospectively randomized into 2 groups. Separation of the greater omentum from the superior layer of the transverse mesocolon was achieved in Group I (n = 20) patients by the monopolar cauterization dissection technique whereas in Group II (n = 20) patients by the hydrodissection-facilitated monopolar cauterization. No significant difference was found between the 2 groups in terms of age, gender, body mass index (BMI), type of surgical technique, or the number of resected lymph nodes (P &amp;gt; 0.05). The difference between the 2 dissection techniques was not statistically significant when compared according to the number of iatrogenic mesocolonic defects, extension of the defects, or the time period required for the separation of greater omentum from the superior layer of the transverse mesocolon (P &amp;gt; 0.05). The overall survival was not significantly different between the 2 dissection techniques (P &amp;gt; 0.05). Hydrodissection is a safe technique that can be applied as an adjunct to electrocauterization to facilitate the dissection in the correct plane during resection of the mesogastrium.

The impact of temperature dependent electrical conductivity in radiofrequency ablation treatment planning

Introduction Radiofrequency ablation (RFA) for cancer therapy is usually performed under a medical imaging modality to evaluate tissue necrosis, albeit with some limitations. In recent years, the advancements in computational resources and their wide availability have rendered individualized treatment planning for RFA feasible. However, this approach involves several limitations and approximations, as well. Purpose In the current study we aim at elucidating the importance of assuming a temperature dependence for the electrical conductivity and its effect in the predicted final temperature distribution and necrotic volume. Materials and methods The simulated model is a two-compartmental one, which assumes different electrical conductivity in the spherical tumor and the surrounding healthy tissue. A single electrode is entered inside the tumor (monopolar technique). The Laplace and the Pennes bioheat-transfer equations are solved numerically with the finite difference method coded in C, after applying the appropriate boundary conditions. It is assumed that the electrical conductivity in both compartments changes with temperature. Results The calculated temperature rise and necrosis volume (as assessed by CEM43 °C above a threshold) change considerably when the electrical conductivity varies with temperature. In fact, various formulations for this temperature dependence have been suggested and they can result in differences larger than 15% in the treatment outcome indicators. Conclusion Currently, it is possible to achieve individualized treatment planning for RFA. However, there is scarce information from the literature on the changes of tissue properties at ablative temperatures, which could lead to more accurate predictions of the treatment outcome.

Comparison between Post-tonsillectomy Bleeding of Three Different Techniques in Children

Introduction: Post-tonsillectomy bleeding remains the most serious complication of tonsillectomy. The rate of post tonsillectomy bleeding varies with different technique. The common used techniques are the bipolar, monopolar and cold. Methods: This was a retrospective case series study based on chart review of children under 14 years who underwent tonsillectomy during the period between January 2010 to December 2011 at King Abdulaziz Medical City (KAMC), Riyadh, Saudi Arabia – ENT department. The charts of all the patients were reviewed by the student and the data form filled for included patients for the age, gender, indications for tonsillectomy, previous surgery, medications, admission type, technique used which are the bipolar, monopolar and cold technique and complications. Results: Out of 60 patients reviewed, post tonsillectomy bleeding was reported in 16 (27%). Indications for tonsillectomy were six indications and most common one was recurrent adenotonsillitis in 27 (46%). Intraoprative bleeding was 8 cases (13%) which was the most common type of bleeding and there was no significant difference in post tonsillectomy bleeding between the three techniques (p=0.62). Conclusion: The result showed that there was no significant difference in post tonsillectomy bleeding between the three techniques.

Could Transurethral Resection of the Prostate Using the TURis System Take Over Conventional Monopolar Transurethral Resection of the Prostate? A Randomized Controlled Trial and Midterm Results

To assess whether bipolar transurethral resection of the prostate using the TURis (Olympus, Tokyo, Japan) system demonstrates comparable efficacy and safety reporting 36months of follow-up findings. The trial was registered at University hospital Medical Information Network Clinical Trials Registry in Japan (trial number UMIN 000010801). Patients were randomly selected to undergo transurethral resection of the prostate using either the TURis or the conventional monopolar technique. Primary end points were safety according to operation time, decline of sodium and hemoglobin levels, clot retention, and catheterization time. Secondary end points were efficacy findings for patients after 36months of follow-up. A total of 136 patients were enrolled. Mean operation times were significantly prolonged in the TURis group (68.4 and 79.5minutes for monopolar and TURis groups, respectively; P= .048). Nosignificant differences in the decline of hemoglobin, hematocrit, and perioperative transfusion rates between groups were seen, whereas clot retention (grade 2) after the treatment seemed to occur more often in the monopolar group (7 of 62 [12.3%] in monopolar group vs 1 of 63 [1/8%] in TURis group; P= .061). No case presented symptomatic transurethral resection syndrome in either groups. Continued efficacy at 36months after the treatment could be confirmed for the first time in TURis system, which also seems to be preferable as they produced more clinically favorable outcomes. Nevertheless, the TURis system required significantly more resection time, which might not entirely be a panacea for the treatment of benign prostatic obstruction, especially for patients having larger prostatic volumes.

Histopathologic Comparison of Monopolar versus No-Touch Multipolar Radiofrequency Ablation to Treat Hepatocellular Carcinoma within Milan Criteria

PurposeTo compare histopathologically the completeness of radiofrequency (RF) ablation to treat hepatocellular carcinoma (HCC) with monopolar or multipolar technique. Materials and MethodsThirty-five consecutive patients (mean age, 59 y) with cirrhosis and HCC (n = 59) within Milan criteria received RF ablation and subsequently underwent liver transplantation (LT) for tumor progression or liver failure. Data were extracted retrospectively from a prospective database. Thirty nodules were treated with a monopolar device with internally cooled (n = 17) or perfused (n = 13) electrodes, and 29 were treated with a multipolar technique with internally cooled electrodes based on the “no-touch” concept. This consisted of inserting two or three straight electrodes around the nodule to avoid intratumor puncture to the greatest extent possible. Effectiveness of the three devices was compared by histopathologic examination of explants. Fisher exact and χ2 tests and multivariate logistic regression analysis were performed. ResultsMean sizes of nodules ablated (25, 22, and 21.6 mm) and median times from ablation to LT (11, 7.5, and 8.4 months) for patients treated with the monopolar internally cooled electrode device (MoICD), monopolar perfused electrode device (MoPED), and multipolar internally cooled electrode device (MuICD), respectively, were similar (P = .8 and P = .9, respectively). Pathologic examination showed complete necrosis for eight of 17 and six of 13 nodules treated with the MoICD and MoPED, respectively, versus 26 of 29 treated with the MuICD (P = .0019). In multivariate analysis, RF technique remained the predictive factor for complete necrosis (P = .005). ConclusionsAblation of small HCCs with multipolar RF ablation based on the no-touch concept improves the rate of complete necrosis during pathologic examination compared with monopolar techniques.