scholarly journals Stereotactic navigation versus ultrasound guidance in placing IRE applicators in a liver phantom

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
David Stillström ◽  
Benjamin Eigl ◽  
Jacob Freedman

AbstractThe aim of this study was to compare the accuracy of stereotactic CT-guided navigation and ultrasound guided navigation for placing electrodes in Irreversible electroporation in a liver phantom. A liver phantom with multiple tumours was used and interventionists placed four IRE electrodes around each tumour guided either by stereotactic CT-guided navigation or ultrasound. The goal was to place them in a perfect 20 × 20 mm square with parallel electrodes. After each treatment, a CT-scan was performed. The accuracy in pairwise electrode distance, pairwise parallelism and time per tumour was analysed. Eight interventionists placed four electrodes around 55 tumours, 25 with ultrasound and 30 with stereotactic CT-guided navigation. 330 electrode pairs were analysed, 150 with ultrasound and 180 with stereotactic CT-navigation. The absolute median deviation from the optimal distance was 1.3 mm (range 0.0 to 11.3 mm) in the stereotactic CT-navigation group versus 7.1 mm (range 0.3 to 18.1 mm) in the Ultrasound group (p < 0.001). The mean angle between electrodes in each pair was 2.7 degrees (95% CI 2.4 to 3.1 degrees) in the stereotactic CT-navigation group and 5.5 degrees (95% CI 5.0 to 6.1 degrees) in the Ultrasound group (p < 0.001). The mean time for placing the electrodes was 15:11 min (95% CI 13:05 to 17:18 min) in the stereotactic CT-navigation group and 6:40 min (95% CI 5:28 to 7:52 min) in the Ultrasound group. The use of stereotactic CT-navigation in placing IRE-electrodes in a liver phantom is more accurate, but more time consuming, compared to ultrasound guidance.

1988 ◽  
Vol 60 (01) ◽  
pp. 039-043 ◽  
Author(s):  
L Mandelbrot ◽  
M Guillaumont ◽  
M Leclercq ◽  
J J Lefrère ◽  
D Gozin ◽  
...  

SummaryVitamin K status was evaluated using coagulation studies and/ or vitamin IQ assays in a total of 53 normal fetuses and 47 neonates. Second trimester fetal blood samples were obtained for prenatal diagnosis under ultrasound guidance. Endogenous vitamin K1 concentrations (determined by high performance liquid chromatography) were substantially lower than maternal levels. The mean maternal-fetal gradient was 14-fold at mid trimester and 18-fold at birth. Despite low vitamin K levels, descarboxy prothrombin, detected by a staphylocoagulase assay, was elevated in only a single fetus and a single neonate.After maternal oral supplementation with vitamin K1, cord vitamin K1 levels were boosted 30-fold at mid trimester and 60 fold at term, demonstrating placental transfer. However, these levels were substantially lower than corresponding supplemented maternal levels. Despite elevated vitamin K1 concentrations, supplemented fetuses and neonates showed no increase in total or coagulant prothrombin activity. These results suggest that the low prothrombin levels found during intrauterine life are not due to vitamin K deficiency.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Johannes Spille ◽  
Feilu Jin ◽  
Eleonore Behrens ◽  
Yahya Açil ◽  
Jürgen Lichtenstein ◽  
...  

Abstract Background The aim of the study is to evaluate the accuracy of a new implant navigation system on two different digital workflows. Methods A total of 18 phantom jaws consisting of hard and non-warping plastic and resembling edentulous jaws were used to stimulate a clinical circumstance. A conventional pilot-drill guide was conducted by a technician, and a master model was set by using this laboratory-produced guide. After cone beam computed tomography (CBCT) and 3D scanning of the master models, two different digital workflows (marker tray in CBCT and 3D-printed tray) were performed based on the Digital Imaging Communication in Medicine files and standard tessellation language files. Eight Straumann implants (4.1 mm × 10 mm) were placed in each model, six models for each group, resulting in 144 implant placements in total. Postoperative CBCT were taken, and deviations at the entry point and apex as well as angular deviations were measured compared to the master model. Results The mean total deviations at the implant entry point for MTC (marker tray in CBCT), 3dPT (3d-printed tray), and PDG (pilot-drill guide) were 1.024 ± 0.446 mm, 1.027 ± 0.455 mm, and 1.009 ± 0.415 mm, respectively, and the mean total deviations at the implant apex were 1.026 ± 0.383 mm, 1.116 ± 0.530 mm, and 1.068 ± 0.384 mm. The angular deviation for the MTC group was 2.22 ± 1.54°. The 3dPT group revealed an angular deviation of 1.95 ± 1.35°, whereas the PDG group showed a mean angular deviation of 2.67 ± 1.58°. Although there were no significant differences among the three groups (P > 0.05), the navigation groups showed lesser angular deviations compared to the pilot-drill-guide (PDG) group. Implants in the 3D-printed tray navigation group showed higher deviations at both entry point and apex. Conclusions The accuracy of the evaluated navigation system was similar with the accuracy of a pilot-drill guide. Accuracy of both preoperative workflows (marker tray in CBCT or 3D-printed tray) was reliable for clinical use.


2005 ◽  
Vol 17 (4) ◽  
pp. 689-698 ◽  
Author(s):  
Shigekiyo Fujita ◽  
Tetsuro Kawaguchi ◽  
Toshiyuki Uehara ◽  
Kazuhito Fukushima

Background: Platelet hyper-aggregability is an important risk factor for leukoaraiosis. In this study we investigated whether aggravation of leukoaraiosis can be controlled by means of long-term correction of platelet hyper-aggregability.Methods:Twenty-one patients with leukoaraiosis and uncorrected platelet hyper-aggregability were compared with 21 controls matched for age, grade of leukoaraiosis and observation period whose platelet hyper-aggregability was corrected. Platelet aggregability was estimated by an optical analytical method with a nine-stage display using two different concentrations each of adenosine diphosphate (ADP) and collagen (the double ADP method).Results:The mean observation period between two magnetic resonance imaging (MRI) scans for both groups was 4.1 years. In the non-corrected group, moderate to severe aggravation of leukoaraiosis was observed in a large number of patients. In the corrected group, only a small number of patients showed generally mild aggravation of leukoaraiosis. The number of patients showing aggravation of periventricular hyperintensity (PVH) was 7 in 21 in the non-corrected group versus 1 in 21 (p=0.022) in the corrected group, and for aggravation of deep white-matter hyperintensity, these values were 9 in 21 versus 4 in 21, respectively. Thus, the difference was more significant if the degree of aggravation was taken into account.Conclusion:The progress of leukoaraiosis is greatly inhibited by long-term correction of platelet hyper-aggregability.


2020 ◽  
Vol 30 (4) ◽  
pp. 546-551
Author(s):  
Kazuhiro Ito ◽  
Junichi Shimada ◽  
Masanori Shimomura ◽  
Kunihiko Terauchi ◽  
Motohiro Nishimura ◽  
...  

Abstract OBJECTIVES This study aimed to evaluate the safety and reliability of percutaneous computed tomography (CT)-guided lipiodol marking for undetectable pulmonary lesions before video-assisted thoracic surgery (VATS). METHODS We retrospectively analysed the cases of CT-guided lipiodol marking followed by VATS in 9 institutes from May 2006 to March 2018. Lipiodol (0.2–0.5 ml) was percutaneously injected closely adjacent to undetectable pulmonary lesions with computed-tomography guidance. Lipiodol spots were identified using C-arm-shaped fluoroscopy during VATS. We grasped the lipiodol spots, including the target lesions, with ring-shaped forceps and resected them. RESULTS Of 1182 lesions, 1181 (99.9%) were successfully marked. In 1 case, the injected lipiodol diffused, and no spot was created. Of the 1181 lesions, 1179 (99.8%) were successfully resected with intraoperative fluoroscopy. Two lipiodol spots were not detected because of the lipiodol distribution during the division of pleural adhesions. The mean lesion size was 9.1 mm (range 1–48 mm). The mean distance from the pleural surface was 10.2 mm (range 0–43 mm). Lipiodol marking-induced pneumothorax occurred in 495 (57.1%) of 867 cases. Of these, chest drainage was required in 59 patients (6.8%). The other complications were 19 (2.2%) cases of bloody sputum, 3 (0.35%) cases of intravascular air, 1 (0.12%) case of pneumonia and 1 (0.12%) case of cerebral infarction. There were no lipiodol marking-induced deaths or sequelae. CONCLUSIONS Preoperative CT-guided lipiodol marking followed by VATS resection was shown to be a safe and reliable procedure with a high success rate and acceptably low severe complication rate.


2019 ◽  
Author(s):  
Jun Ding ◽  
Jing Xu ◽  
Wei Ma ◽  
Bingwei Chen ◽  
Peigen Yang ◽  
...  

Abstract Background : The optimal dosage for cryoablation of atrial fibrillation (Cryo-AF) is still unknown. To evaluate the efficacy of an individualized freeze duration, we compared the clinical outcome of patients treated with a time-to-pulmonary vein isolation (TT-PVI) or temperature-guided ablation protocol to the outcome of patients treated with a conventional ablation protocol. Methods: A total of 164 consecutive patients were included in the study. One method employed was a conventional dosing protocol (at least 2 applications of 180 seconds each)(the Cryo-AF Conventional group n=84), and the second method had a shorter protocol that was based on the TT-PVI or achievement of -40°C within 60 seconds (the Cryo-AF Dosing group n=80). Results: We treated 656 pulmonary veins (PVs) with 1420 cryotherapy applications. The mean number of applications per patient was 8.7±0.8, with no difference between groups (Cryo-AF Conventional , 8.7±0.8 versus Cryo-AF Dosing ,8.6±0.8; P =0.359). The Cryo-AF Dosing group required significantly less total cryotherapy application time (990.60±137.77versus 1501.58±89.60 seconds; P <0.001) and left atrial dwell time (69.91±6.91 versus 86.48±7.03 minutes; P <0.001) than the Cryo-AF Conventional group. Additionally, the Cryo-AF Dosing group required significantly less total procedure time (95.03±6.50 versus 112.43±7.11 minutes; P <0.001). We observed acute ATP-induced or spontaneous vein electric reconnections in 13 veins (1.98%) after 20 minutes. The reconnection rates between the Cryo-AF Conventional and Cryo-AF Dosing groups were similar in that 2.98% and 0.94% of the initially isolated veins were reconnected, respectively, ( P =0.061). There was no difference in the recurrence rate of free atrial arrhythmia after a 1-year follow-up, which were 78.75% in the Cryo-AF Dosing group versus 78.57% in the Cryo-AF Conventional group ( P =0.978). Conclusion: A novel Cryo-AF dosing protocol guided by temperature or the TT-PVI can be used to individualize an ablation strategy. This new protocol can lead to a significant reduction in duration of the procedure, the cryoenergy dosage and the left atrial dwell time. The procedure had equal safety and similar acute and 1-year follow-up outcomes compared to the conventional approach.


2020 ◽  
Vol 14 (4) ◽  
pp. 466-474
Author(s):  
Shanmuganathan Rajasekaran ◽  
Dilip Chand Raja Soundararajan ◽  
Ajoy Prasad Shetty ◽  
Rishi Mugesh Kanna

Study Design: Prospective observational study.Purpose: To assess the safety, efficacy, and benefits of computed tomography (CT)-guided C1 fracture fixation.Overview of Literature: The surgical management of unstable C1 injuries by occipitocervical and atlantoaxial (AA) fusion compromises motion and function. Monosegmental C1 osteosynthesis negates these drawbacks and provides excellent functional outcomes.Methods: The patients were positioned in a prone position, and cranial traction was applied using Mayfield tongs to restore the C0–C2 height and obtain a reduction in the displaced fracture fragments. An intraoperative, CT-based navigation system was used to enable the optimal placement of C1 screws. A transverse rod was then placed connecting the two screws, and controlled compression was applied across the fixation. The patients were prospectively evaluated in terms of their clinical, functional, and radiological outcomes, with a minimal follow-up of 2 years.Results: A total of 10 screws were placed in five patients, with a mean follow-up of 40.8 months. The mean duration of surgery was 77±13.96 minutes, and the average blood loss was 84.4±8.04 mL. The mean combined lateral mass dislocation at presentation was 14.6±1.34 mm and following surgery, it was 5.2±1.64 mm, with a correction of 9.4±2.3 mm (<i>p</i> <0.001). The follow-up CT showed excellent placement of screws and sound healing. There were no complications and instances of AA instability. The clinical range of movement at 2 years in degrees was as follows: rotation to the right (73.6°±9.09°), rotation to the left (71.6°±5.59°), flexion (35.4°±4.5°), extension (43.8°±8.19°), and lateral bending on the right (28.4°±10.45°) and left (24.8°±11.77°). Significant improvement was observed in the functional Neck Disability Index from 78±4.4 to 1.6±1.6. All patients returned to their occupation within 3 months.Conclusions: Successful C1 reduction and fixation allows a motion-preserving option in unstable atlas fractures. CT navigation permits accurate and adequate monosegmental fixation with excellent clinical and radiological outcomes, and all patients in this study returned to their preoperative functional status.


Author(s):  
Hao Wang ◽  
Ran Peng ◽  
Xuemin Li ◽  
Yuxia Wang ◽  
Yuliang Jiang ◽  
...  

ABSTRACT The aim of this study was to investigate the safety and accuracy of computed tomography (CT)-guided 125I seed implantation assisted by a three-dimensional printing non-coplanar template (3D-PNCT) for treating pelvic locally recurrent rectal cancer (LRRC) patients. A total of 13 patients with 18 masses received 125I seed implantation. The dosimetric parameters of pre-implantation and post-implantation were calculated to evaluate the quality of 125I seed implantation. Doses delivered to the organs at risk (OAR) were also calculated. Differences between pre-implantation and post-implantation were compared by the paired t-test. The mean number of 125I seeds pre-implantation and post-implantation was 67.1 and 68.8, respectively. The mean values of D90 (dose that was delivered to 90% of the target volume), D100 (dose that was delivered to 100% of the target volume), V100 (the target volume receiving 100% of the prescription dose) and V150 (the target volume receiving 150% of the prescription dose) pre-implantation and post-implantation were 136.6 and 135.2 Gy, 63.5 and 71.0 Gy, 90.3% and 90.3% and 62.1% and 62.2%, respectively. Dosimetric outcomes were evaluated quantitatively using the dose volume indices, i.e. coverage index (CI), external volume index (EI) and relative dose homogeneity index (HI). The mean values of those indices pre-implantation and post-implantation were 0.62 and 0.61, 0.31 and 0.33, and 0.31 and 0.31, respectively. The mean doses delivered to OAR pre-implantation and post-implantation for the bladder (D2cc) and bowel (D2cc) were 33.4 and 34.4 Gy, and 58.6 and 61.8 Gy, respectively. The parameters mentioned above fitted well, and no significant difference was found among them. It is concluded that CT-guided 125I seed implantation assisted by 3D-PNCT could be a safe and accurate salvage modality for treating LRRC patients; the ideal pre-prescription dose could be achieved. Also, addition of 3D-PNCT could minimize radiation damage to the surrounding normal tissues.


Hand Surgery ◽  
2013 ◽  
Vol 18 (03) ◽  
pp. 375-379 ◽  
Author(s):  
Muntasir Mannan Choudhury ◽  
Shian Chao Tay

Surgical treatment for trigger finger involves division of the A1 pulley. Some surgeons perform an additional step of traction tenolysis by sequentially bringing the flexor digitorum superficialis and flexor digitorum profundus tendons out of the wound gently with a Ragnell retractor. There is currently no study which states whether flexor tendon traction tenolysis should be routinely performed or not. The objective of this study is to compare the outcome in patients who have traction tenolysis performed (A group) versus those who did not have traction tenolysis (B group) performed. It was noted that even though the mean total active motion (TAM) for the B group in our study was lower preoperatively, it was consistently higher than the A group in all the 3 post-operative visits demonstrating a better outcome in the B group. Even though it was not statistically significant, our data also showed that patients with traction tenolysis appeared to have more postoperative pain compared to those without.


2021 ◽  
Vol 94 (1121) ◽  
pp. 20200445
Author(s):  
Dimitrios Filippiadis ◽  
George Charalampopoulos ◽  
Athanasios Tsochatzis ◽  
Lazaros Reppas ◽  
Argyro Mazioti ◽  
...  

Objectives: To retrospectively evaluate feasibility and safety of CT-guided percutaneous radiofrequency ablation (RFA) of metastatic lymph nodes (LN) in terms of achieving local tumor control. Methods: Institutional database research identified 16 patients with 24 metastatic LNs who underwent percutaneous CT-guided radiofrequency ablation. Mean patient age was 66.6 ± 15.70 years (range 40–87) and male/female ratio was 8/8. Contrast-enhanced CT or MRI was used for post-ablation follow-up. Patient and tumor characteristics and RFA technique were evaluated. Technical and clinical success on per tumor and per patient basis as well as complication rates were recorded. Results: Mean size of the treated nodes was 1.78 ± 0.83 cm. The mean number of tumors per patient was 1.5 ± 0.63. The mean procedure time was 56.29 ± 24.27 min including local anesthesia, electrode(s) placement, ablation and post-procedural CT evaluation. Median length of hospital stay was 1.13 ± 0.34 days. On a per lesion basis, the overall complete response post-ablation according to the mRECIST criteria applied was 75% (18/24) of evaluable tumors. Repeat treatment of an index tumor was performed on two patients (three lesions) with complete response achieved in 87.5% (21/24) of evaluable tumors following a second RFA. On a per patient basis, disease progression was noted in 10/16 patients at a mean of 13.9 ± 6.03 months post the ablation procedure. Conclusion: CT-guided percutaneous RFA for oligometastatic LNs is a safe and feasible therapy. Advances in knowledge: With this percutaneous therapeutic option, metastatic LNs can be eradicated with a very low complication rate.


2019 ◽  
Vol 11 ◽  
pp. 175628721983836 ◽  
Author(s):  
Jeffrey D. Campbell ◽  
Bruce J. Trock ◽  
Adam R. Oppenheim ◽  
Ifeanyichukwu Anusionwu ◽  
Ronak A. Gor ◽  
...  

Background: The aim of this study was to perform a meta-analysis of randomized controlled trials (RCTs) that evaluate the efficacy of low-intensity extracorporeal shock wave therapy (LiESWT) for the treatment of erectile dysfunction (ED). Materials and methods: A comprehensive search of PubMed, Medline, and Cochrane databases was performed from November 2005 to July 2018. RCTs evaluating efficacy of LiESWT in the treatment of ED were selected. The primary outcomes were the mean difference between treatment and sham patients in the International Index of Erectile Function-Erectile Function (IIEF-EF) domain score 1 month after treatment, and the mean change in IIEF-EF from baseline to 1 month post-treatment. The secondary analysis considered the percentage of men whose erectile hardness score (EHS) changed from <2 at baseline to >3 after treatment. All analyses used a random effects method to pool study-specific results. Results: A total of seven RCTs provided data for 607 patients. The mean IIEF-EF 1 month post-treatment ranged from 12.8 to 22.0 in the treatment group versus 8.17–16.43 in the sham group. The mean difference between the treatment and sham groups at the 1 month follow up was a statistically significant increase in IIEF-EF of 4.23 ( p = 0.012). Overall, five of the seven trials provided data on the proportion of patients with baseline EHS <2 who improved to EHS >3 at 1 month post-treatment. The proportions ranged from 3.5 to 90% in the treatment group versus 0–9% in the sham group and the pooled relative risk of EHS improvement for the treated versus sham group was 6.63 ( p = 0.0095). No significant adverse events were reported. Conclusions: This is the first meta-analysis that evaluates RCTs exploring LiESWT as a treatment modality strictly for ED. This therapeutic strategy appears to be well tolerated with short-term benefits. However further studies exploring specific treatment regimens and long-term outcomes are needed.


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