"Honey Pot"-Like Lesion Formation: Impact of Catheter Contact Angle on Lesion Formation by Novel Diamond-embedded Temperature-controlled Ablation Catheter in a Porcine Experimental Model

BACKGROUND

Novel diamond-embedded catheter enables precise temperature-controlled ablation. However, the effects of contact angle on lesion formation of this catheter are poorly understood.

OBJECTIVE

This study evaluated lesion formation using the temperature-controlled ablation catheter embedded with diamond at different angles in a porcine experimental model.

METHODS

We used freshly sacrificed porcine hearts, and radiofrequency catheter ablation was performed at 50 watts for 15 s at an upper-temperature setting of 60°C. The contact force (5, 10, and 30 g) and catheter contact angles (30°, 45°, and 90°) were changed in each set (n = 13 each). The surface width, maximum lesion width, lesion depth, surface area, distance from the distal edge to the widest area, and impedance drop were evaluated.

RESULTS

The surface width and maximum lesion width were longer at 30° than at 90° (p<0.05). There were no significant differences in the lesion depth by catheter angle except at 30 g. The surface area was larger at 30° than at 90° (p<0.05). The distance from the distal edge to the widest area was longer at 30° than at 90° (p<0.05). There were no significant differences in the impedance drop according to the catheter angle.

CONCLUSION

With the diamond-embedded temperature-controlled ablation catheters, the lesion width increased at a shallower contact angle, whereas the lesion depth did not. The surface area also increased at a shallower contact angle. This catheter created a large ablation lesion on the proximal side of the catheter, which looked like a "Honey pot."

Characteristics of positive horizontal margins in patients who underwent colorectal endoscopic submucosal dissection

Objectives

Endoscopic submucosal dissection (ESD) enables en bloc resection of colorectal neoplasms, but occasionally results in positive horizontal margins (HMs). However, the site of the resected specimen that tends to be positive for HM has not been investigated. We aimed to clarify the characteristics associated with HMs in lesions resected en bloc with ESD.

Methods

Patients with colorectal neoplasms who underwent en bloc resection with ESD were included in this study. The patients were divided into negative HMs (HM0) and positive or indeterminate HMs (HM1) groups. The characteristics associated with HM1 resection were investigated. In addition, the local recurrence rate during endoscopic follow-up for >6 months after ESD was observed.

Results

In total, 201 lesions were analyzed in 189 patients (HM0, 189 lesions; HM1, 12 lesions). The HM1 group had a significantly larger median lesion diameter (25 vs. 55 mm; p < 0.001) and more lesions with >50% circumference than did the HM0 group (p < 0.001). Furthermore, the prevalence of severe fibrosis was significantly higher in the HM1 group than in the HM0 group (p < 0.001). Positive horizontal sites of the resected specimens were more frequent at the oral and anal sites than at the lateral sites. No local recurrences were observed in either group.

Conclusions

The characteristics associated with HM1 depended on lesion size, particularly lesions with >50% circumference, and submucosal fibrosis.

Impact of contact force on the lesion characteristics of very high-power short-duration ablation using a QDOT-MICRO catheter

Background

Lesion size is reported to become larger as contact force (CF) increases. However, this has not been systematically evaluated in temperature-guided very high-power short-duration (vHPSD) ablation, which was therefore the purpose of this study.

Methods

Radiofrequency applications (90 W/4 s, temperature-control mode) were performed in excised porcine myocardium with four different CFs of 5, 15, 25, and 35 g using QDOT-MICRO™ catheter. Ten lesions for each combination of settings were created, and lesion metrics and steam-pops were compared.

Results

A total of 320 lesions were analyzed. Lesion depth, surface area, and volume were smallest for CF of 5 g than for 15, 25, and 35 g (depth: 2.7 mm vs. 2.9 mm, 3.0 mm, 3.15 mm, p < .01; surface area: 38.4 mm2 vs. 41.8 mm2, 43.3 mm2, 41.5 mm2, p < .05; volume: 98.2 mm3 vs. 133.3 mm3, 129.4 mm3, 126.8 mm3, p < .01 for all pairs of groups compared to CF = 5 g). However, no significant differences were observed between CFs of 15-35 g. Average power was highest for CF of 5 g, followed by 15, 25, and 35 g (83.2 W vs. 82.1 W vs. 77.1 W vs. 66.1 W, p < .01 for all pairs), reflecting the higher incidence of temperature-guided power titration with greater CFs (5 g:8.8% vs. 15 g:52.5% vs. 25 g:77.5% vs. 35 g:91.2%, p < .01 for all pairs except for 25 g vs. 35 g). The incidence of steam-pops did not significantly differ between four groups (5 g:3.8% vs. 15 g:10% vs. 25 g:6.2% vs. 35 g:2.5%, not significant for all pairs).

Conclusions

For vHPSD ablation, lesion size does not become large once the CF reaches 15 g, and the risk of steam-pops may be mitigated through power titration even in high CFs.

Effectiveness of Injectable Platelet-Rich Fibrin in the Treatment of Oral Lichen Planus: A Systematic Review and Meta-Analysis

Oral lichen planus (OLP) is a chronic inflammatory condition affecting the oral mucosa. The current review investigated the potential effectiveness of injectable platelet-rich fibrin (i-PRF) as a treatment for OLP when compared to other interventions. The current review adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive search strategy was implemented across databases such as PubMed, Embase, Scopus, Web of Science, CINAHL, and Google Scholar. The search utilized a combination of Boolean operators (AND, OR) and Medical Subject Headings (MeSH) terms to capture relevant studies. Comparative clinical studies focusing on i-PRF as a treatment for OLP and other interventions were included. Outcomes assessed were pain, surface area of lesions, and patient satisfaction. Review Manager 5.4 was used for statistical analysis. The Risk of Bias 2.0 (RoB 2.0) tool was used to assess the methodological quality of the studies. Three studies were included for the final analysis. The findings indicated that both the i-PRF and comparison treatment groups demonstrated reductions in pain and lesion size. The post-treatment Visual Analogue Scale (VAS) scores showed a decrease in pain intensity, and there was an improvement in lesion extension in the i-PRF-treated sites. The results also revealed increased patient satisfaction with i-PRF treatment. Adverse effects were not reported or specified in the included studies. Quantitative analysis for pain (VAS) showed a mean difference of 0.38 (95% CI: 0.63-1.40), but there was no significant difference between the i-PRF and control groups at p=0.46. Though intragroup differences showed statistically significant differences between pre and post intervention, intergroup differences were not significant for any of the assessed outcomes. The findings from this study suggest that i-PRF holds promise as a potential treatment for OLP. The use of i-PRF resulted in pain reduction, lesion size improvement, and increased patient satisfaction. However, it is important to consider the limitations of the included studies, such as variability in study designs, small sample sizes, and the limited number of studies.

Safety verification of a novel irrigation catheter with flexible tip of laser-cut kerfs and contact force sensor

BACKGROUND AND AIMS

The safety evaluation of TactiFlex, a novel contact-force sensing catheter with a flexible 4-mm tip irrigated through laser-cut kerfs, has been ongoing. This study aimed to verify the safety of this type of catheter.

METHODS

Study 1: Radiofrequency (RF) applications at a range of powers (30-50 W), contact forces (10-20 g), and durations (10-60 s) using perpendicular/parallel catheter orientation with half-normal (HNS) or normal saline irrigation were compared between TactiFlex (4-mm tip) and TactiCath (3.5-mm tip) with temperature-controlled mode in excised porcine hearts. Study 2: The relation between RF applications using TactiFlex and the incidence of steam-pops in the real clinical cases were examined.

RESULTS

Study-1: 576 RF lesions were examined. TactiFlex demonstrated a significantly lower risk of steam-pops (5[1.7%] vs. 59[20.5%], p < .0001). Compared to 3.5-mm-tip catheter (TactiCath), 4-mm-tip catheter (TactiFlex) produced smaller lesion volume at perpendicular (193[98-554]mm3 vs. 263[139-436]mm3 , p < .0001), but relatively similar lesion volume at parallel contact (243[105-443]mm3 vs. 278[180-440]mm3 , p = .06). HNS-irrigation tended to increase the lesion volume in both catheters and to increase the incidence of steam-pops with TactiCath, but not with TactiFlex. The cut-off value of %impedance-drop ( = absolute impedance-drop/initial impedance) of 20% predicted steam-pops with a sensitivity = 100% and specificity = 89.6% in TactiFlex. Study-2: 5496 RF applications in 84 patients (51AFs/8ATs/3AVNRTs/4AVRTs/17PVCs/4VTs) using TactiFlex were analyzed. Four steam-pops (0.07%) in three patients with pericardial effusion were observed (%impedance-drop = 24%/26%/29%/35%, respectively). The cut-off value of %impedance-drop = 20%, derived from ex-vivo study, showed sensitivity = 100% and specificity = 90.1% in detecting steam-pops.

CONCLUSION

TactiFlex reduced the risk of steam-pops than TactiCath. %impedance-drop ≤ 20% may be reasonable for safely use with a sufficient safety margin. For 4-mm-tip catheter, parallel-contact may be recommended for larger lesion creation.

The influence of electrode-tissue-coverage on RF lesion formation and local impedance: Insights from an ex vivo model

BACKGROUND

The influence of power, duration and contact force (CF) on radiofrequency (RF) lesion formation is well known, whereas data on local impedance (LI) and electrode-tissue-coverage (ETC) is scarce. The objective was to investigate their effect on lesion formation in an ex vivo model.

METHODS AND RESULTS

An ex vivo model was developed utilizing cross-sections of porcine heart preparations and a force-sensing, LI-measuring catheter. N = 72 lesion were created systematically varying ETC (minor/full), CF (1-5 g, 10-15 g, 20-25 g) and power (20 W, 30 W, 40 W, 50 W). In minor ETC, the distal tip of the catheter was in electric contact with the tissue, in full ETC the whole catheter tip was embedded within the tissue. Lesion size and all parameters were measured once per second (n = 3320). LI correlated strongly with lesion depth (r = -0.742 for ΔLI; r = 0.781 for %LI-drop). Lesions in full ETC were significantly wider and deeper compared to minor ETC (p < .001) and steam pops were more likely. Baseline LI, ΔLI, and %LI-drop were significantly higher in full ETC (p < .001). In lesions resulting in steam pops, baseline LI, and ΔLI were significantly higher. The influence of CF on lesion size was higher in minor ETC than in full ETC.

CONCLUSIONS

ETC is a main determinant of lesion size and occurrence of steam pops. Baseline LI and LI-drop are useful surrogate parameters for real-time assessment of ETC and ΔLI correlates strongly with lesion size.

Effects of Host and Weather Factors on the Growth Rate of Septoria nodorum Blotch Lesions on Winter Wheat

Septoria nodorum blotch (SNB), caused by Parastagonospora nodorum, is a major disease of winter wheat that occurs frequently in the central and southeastern United States. Quantitative resistance to SNB in wheat is determined by various disease resistance components and their interaction with environmental factors. A study was conducted in North Carolina from 2018 to 2020 to characterize SNB lesion size and growth rate and to quantify the effects of temperature and relative humidity on lesion expansion in winter wheat cultivars with different levels of resistance. Disease was initiated in the field by spreading P. nodorum-infected wheat straw in experimental plots. Cohorts (groups of foliar lesions arbitrarily selected and tagged as an observational unit) were sequentially selected and monitored throughout each season. Lesion area was measured at regular intervals, and weather data were collected using in-field data loggers and the nearest weather stations. Final mean lesion area was approximately seven times greater on susceptible than on moderately resistant cultivars, and lesion growth rate was approximately four times higher on susceptible than on moderately resistant cultivars. Across trials and cultivars, temperature had a strong effect of increasing lesion growth rates (P < 0.001), while relative humidity had no significant effect (P = 0.34). Lesion growth rate declined slightly and steadily over the duration of cohort assessment. Our results demonstrate that restricting lesion growth is an important component of SNB resistance in the field and suggest that the ability to limit lesion size may be a useful breeding goal.

Comparison of three different approaches to very high-power short-duration ablation using the QDOT-MICRO catheter

BACKGROUND/OBJECTIVES

The QDOT-MICRO™ catheter allows very high-power and short-duration (vHPSD) ablation. This study aimed to investigate lesion characteristics using different ablation settings.

METHODS

Radiofrequency applications (90 W/4 s, temperature-control mode with 55°C or 60°C target) were performed in excised porcine myocardium using three different approaches: single (SA), double nonrepetitive (DNRA), and double repetitive applications (DRA). Applications were performed with an interval of 1 min for DNRA, and without interval for DRA.

RESULTS

A total of 480 lesions were analyzed. Lesion depth and volume were largest for DRA followed by DNRA and SA regardless of catheter direction (depth: 3.8 vs. 3.3 vs. 2.6 mm, p < .001 for all comparisons; volume: 176.6 vs. 145.1 vs. 97.0 mm³ , p < .001 for all comparisons). Surface area was significantly larger for DRA than for SA (45.1 vs. 38.3 mm² , p < .001) and larger for DNRA than for SA (44.5 vs. 38.3 mm² , p < .001), but was similar between DRA and DNRA (45.1 vs. 44.5 mm² , p = .54). Steam-pops more frequently occurred for DRA than for SA (15.6% vs. 4.4%, p = .004) and DNRA (15.6% vs. 6.9%, p = .061), but the incidence was similar between SA and DNRA (4.4% vs. 6.9%, p = 1). Although surface area and lesion volume were larger in lesions with steam-pops than without steam-pops (46.5 vs. 38.1 mm² , p = .018 and 128.3 vs. 96.8 mm³ , p = .068, respectively), lesions were not deeper (pop(+): 2.5 mm vs. pop(-): 2.6 mm, p = .75).

CONCLUSIONS

DNRA produces larger lesions than SA without increasing the risk of steam-pops. DRA produces the largest lesions among the three groups, but with an increased risk of steam-pops. Even with steam-pops, lesions do not become deeper in vHPSD ablation.

Ex-vivo histopathologic examination of irrigated radiofrequency ablation utilizing half-normal saline of the human heart

INTRODUCTION

Radiofrequency ablation (RFA) utilizing half-normal saline (HNS) irrigation is a promising intervention to circumvent commonly encountered limitations during radiofrequency ablation of deep myocardial substrate. Few studies to date have analyzed the morphologic changes in the human myocardium following HNS RFA.

METHODS AND RESULTS

Three patients with symptomatic ventricular tachycardia (VT) who underwent RFA with HNS irrigation underwent pathological specimen examination at time of autopsy or following native heart explant at the time of cardiac transplantation. Gross evaluation of the heart was performed fresh and after fixation in 10% formalin. A routine examination was performed with fixation in 10% formalin. Sections of lesioned tissue were paraffin embedded and evaluated using standard hematoxylin and eosin (H&E) staining.

CONCLUSION

Irrigated RF ablation with HNS irrigant produces coagulative necrosis as well as several delayed histopathological changes with a deeper field of effective ablation. Transmurality may not be obtained in the ventricular myocardium with endocardial, epicardial, or sequential unipolar HNS ablation.

Assessment of ultrasound shear wave elastography: An animal ex-vivo study

OBJECTIVES

To explore the influence of the surrounding environment of the target tissue, lesion size, and rectangular sampling box size on shear wave speed (SWS).

METHODS

The tendon SWS was acquired ex-vivo. Then the tendons were dissected and buried in the couplant (gel) and evaluated by two-dimensional shear wave elastography (2D-SWE). Finally, the tendons were placed in the isolated muscles to simulate the intramuscular lesions, and their elasticity was tested under two rectangular sampling box conditions. The isolated complete liver SWS was acquired. Similarly, the large and small pieces of livers were cut out, placed in the muscles, and assessed by SWE under two rectangular sampling box conditions. The SWS acquired under different conditions was compared. Variability was evaluated using the coefficient of variation (CV). The intraclass correlation coefficient (ICC) was used to evaluate repeatability.

RESULTS

The SWS of the tendons ex-vivo, buried in the couplant and placed in the isolated muscles showed significant differences (p < 0.001). The ex-vivo condition produced the highest SWS and CV values. There were significant differences in SWS of livers with different sizes placed in muscles (p < 0.001). The highest SWS value was associated with small pieces of livers. No significant difference was found in SWS acquired under different rectangular box sizes (p > 0.05).

CONCLUSIONS

Under the present study conditions, the surrounding environment of the target tissue makes a big difference to lesion SWS values. The lesion size will affect the assessment of its inherent elasticity. The size of the sampling frame has no significant effect on the tissue SWS.

Differential Adaptation Has Resulted in Aggressiveness Variation of Calonectria pseudonaviculata on Hosts Buxus, Pachysandra, and Sarcococca

Calonectria pseudonaviculata (Cps) infects Buxus (boxwood), Pachysandra (pachysandra), and Sarcococca spp. (sweet box); yet, how it adapts to its hosts has been unclear. Here, we performed serial passage experiments with the three hosts and measured Cps changes in three aggressiveness components: infectibility, lesion size, and conidial production. The detached leaves of individual hosts were inoculated with isolates (P0) from the originating host, followed by nine serial inoculations of new leaves of the same host with conidia from the infected leaves of the previous inoculation. All boxwood isolates maintained their capability of infection and lesion expansion through the 10 passages, whereas most non-boxwood isolates lost these abilities during the passages. Isolates from plants of origin (*-P0) and their descendants isolated from passages 5 (*-P5) and 10 (*-P10) were used to evaluate aggressiveness changes on all three hosts with cross-inoculation. While post-passage boxwood isolates gave enlarged lesions on pachysandra, sweet box P5 and pachysandra P10 isolates showed reduced aggressiveness on all hosts. Cps appears to be most adapted to boxwood and less adapted to sweet box and pachysandra. These results suggest speciation of Cps, with its coevolutionary pace with the hosts the fastest with boxwood, intermediate with sweet box, and the slowest with pachysandra.

Ablation characteristics and incidence of steam pops with a novel, surface temperature-controlled ablation system in an ex vivo experimental model

BACKGROUND

A novel irrigation catheter (QDOT MICRO™) has been introduced, which enables a surface temperature-controlled ablation combined with tip cooling. However, the detailed description of its complex behavior and effect on the incidence of pops and lesion formation remains elusive. This study aimed to systematically investigate the ablation characteristics, feedback behavior, and incidence of steam pops in a simplified ex vivo swine model.

METHODS

Using swine ventricular tissue perfused with saline at 37°C, we systematically created lesions with 4×3 combinations of the wattage (20, 30, 40, and 50 W) and contact force (CF, 10, 30, and 50 g). Ablation was continued for either 120 s or until a steam pop occurred and repeated 10 times with each setting. The lesion geometry, ablation index, feedback dynamics, and conditions underlying the steam pops were measured and analyzed.

RESULTS

Steam pops occurred particularly frequently in combinations of a low CF and high power (10 g vs. 30 g+50 g [p < .0001]; 40 W+50 W vs. 20 W+30 W [p < .0001]). Failure to activate a feedback process was associated with a 5.1 times higher incidence of steam pops (21/109 vs.11/11, [95% CI 3.499-7.716], p < .0001). The wattage feedback was particularly evident with a high CF (30 and 50 g) and high initial wattage (40 and 50 W). The average delivered wattage at 27 W predicted the occurrence of steam pops.

CONCLUSION

The temperature-controlled ablation with the QDOT MICRO™ demonstrated a complex feedback behavior, which contributed to a reduced incidence of steam pops and prolonged lead time to the pops.

Accuracy of sonography for non-invasive detection of ovarian and deep endometriosis using #Enzian classification: prospective multicenter diagnostic accuracy study

OBJECTIVE

To compare the preoperative detection of endometriosis using transvaginal sonography (TVS) supplemented by transabdominal sonography (TAS) with surgical assessment of disease, using the #Enzian classification for endometriosis.

METHODS

This was a prospective multicenter diagnostic accuracy study of women undergoing TVS/TAS and radical surgery for deep endometriosis (DE) at different tertiary referral centers. The localization and grade of severity of the endometriotic lesions and adhesions were described according to the criteria of the #Enzian classification, both at preoperative ultrasound examination and during surgery. According to the #Enzian classification, the small pelvis is divided into three compartments for DE: A (rectovaginal septum and vagina); B (uterosacral and cardinal ligaments, parametrium and pelvic sidewalls); and C (rectum). In addition, further locations (F) are classified as adenomyosis (FA), urinary bladder involvement (FB) and ureteric involvement with signs of obstruction (FU). Other intestinal locations (FI) and other extragenital locations (FO) are also included. Ovarian endometriosis and adhesions at the level of the tubo-ovarian unit are listed as O and T, respectively. The #Enzian grade of severity (Grade 1-3) was determined for #Enzian compartments O, T, A, B and C based on the size of the lesion or the severity of the adhesions. Concordance between preoperative assessment using TVS/TAS and evaluation at surgery was assessed. The sensitivity, specificity, positive and negative predictive values and accuracy of TVS/TAS in the detection of endometriotic lesions/adhesions in the different #Enzian compartments were calculated.

RESULTS

In total, 745 women were included in the analysis. Preoperative TVS/TAS and surgical findings showed a concordance rate ranging between 86% and 99% for the presence or absence of endometriotic lesions/adhesions, depending on the evaluated #Enzian compartment. The concordance rate between TVS and surgery ranged between 71% and 92% for different severity grades, in #Enzian compartments O, T, A, B and C. Determining the presence or absence of adhesions at the level of the tubo-ovarian unit and classifying them accurately as Grade 1, 2 or 3 on TVS was more difficult than determining the presence and severity of endometriotic lesions in #Enzian compartments O, A, B and C. The sensitivity of TVS/TAS for the detection of endometriotic lesions ranged from 50% (#Enzian compartment FI) to 95% (#Enzian compartment A), specificity from 86% (#Enzian compartment T_left ) to 99% (#Enzian compartment FI) and 100% (#Enzian compartments FB, FU and FO), positive predictive value from 90% (#Enzian compartment T_right ) to 100% (#Enzian compartment FO), negative predictive value from 74% (#Enzian compartment B_left ) to 99% (#Enzian compartments FB and FU) and accuracy from 88% (#Enzian compartment B_right ) to 99% (#Enzian compartment FB).

CONCLUSIONS

The localization and severity of endometriotic lesions/adhesions, as described and classified according to the #Enzian classification, can be diagnosed accurately and non-invasively using TVS/TAS. The #Enzian classification provides a uniform classification system for describing endometriotic lesions, which can be used both at TVS/TAS and during surgical evaluation. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Catheter contact angle influences local impedance drop during radiofrequency catheter ablation: Insight from a porcine experimental study with 2 different LI-sensing catheters

BACKGROUND

Local impedance (LI) can indirectly measure catheter contact and tissue temperature during radiofrequency catheter ablation (RFCA). However, data on the effects of catheter contact angle on LI parameters are scarce. This study aimed to evaluate the influence of catheter contact angle on LI changes and lesion size with 2 different LI-sensing catheters in a porcine experimental study.

METHODS

Lesions were created by the INTELLANAV MiFi™ OI (MiFi) and the INTELLANAV STABLEPOINT™ (STABLEPOINT). RFCA was performed with 30 watts and a duration of 30 seconds. The CF (0, 5, 10, 20, and 30 g) and catheter contact angle (30°, 45°, and 90°) were changed in each set (n=8 each). The LI rise, LI drop, and lesion size were evaluated.

RESULTS

The LI rise increased as CF increased. There was no angular dependence with the LI rise under all CFs in the MiFi. On the other hand, the LI rise at 90° was lower than at 30° under 5 and 10 g of CF in STABLEPOINT. The LI drop increased as CF increased. Regarding the difference in catheter contact angles, the LI drop at 90° was lower than that at 30° for both catheters. The maximum lesion widths and surface widths were smaller at 90° than at 30°, whereas there were no differences in lesion depths.

CONCLUSION

The LI drop and lesion widths at 90° were significantly smaller than those at 30°, although the lesion depths were not different among the 3 angles for the MiFi and STABLEPOINT. This article is protected by copyright. All rights reserved.

Transvaginal sonography determines accurately extent of infiltration of rectosigmoid deep endometriosis

OBJECTIVE

To investigate the agreement of measurements of the three diameters of rectosigmoid deep endometriosis (DE) lesions between presurgical evaluation using transvaginal sonography (TVS) and postsurgical specimen measurement (PSM).

METHODS

This was a prospective observational multicenter study including symptomatic women undergoing surgical treatment for DE involving the rectosigmoid, by either discoid or segmental resection, from April 2017 to December 2019. TVS was performed presurgically to evaluate lesion size (craniocaudal-midsagittal length, anteroposterior thickness and transverse diameter), in accordance with the International Deep Endometriosis Analysis (IDEA) group consensus statement, and was compared with PSM. The agreement of lesion dimensions between the two methods was assessed by Bland-Altman plots and limits of agreement and additionally by the intraclass correlation coefficient (ICC) and Pearson's correlation coefficient. Systematic and proportional bias was assessed using the paired t-test.

RESULTS

A total of 207 consecutive women were eligible for inclusion. Forty-one women were excluded, leaving 166 women for final analysis. A total of 123 segmental resections and 46 discoid resections were performed (both procedures were performed in three women). The mean difference between TVS and PSM was 0.90 (95% CI, 0.85-0.95) mm for lesion length measurements, 1.03 (95% CI, 0.98-1.09) mm for lesion thickness measurements and 0.84 (95% CI, 0.79-0.89) mm for transverse diameter measurements. Bland-Altman analysis demonstrated good agreement between the two methods for measurements of lesion length. Furthermore, there was good reliability and correlation between TVS and PSM for lesion length measurements, as demonstrated by an ICC of 0.82 (95% CI, 0.75-0.87) and Pearson's correlation coefficient of 0.72 (95% CI, 0.62-0.80), moderate-to-good reliability and correlation for lesion thickness measurements, with an ICC of 0.76 (95% CI, 0.67-0.82) and Pearson's correlation coefficient of 0.61 (95% CI, 0.51-0.70), and poor-to-moderate reliability and correlation for transverse diameter measurements, with an ICC of 0.58 (95% CI, 0.39-0.71) and Pearson's correlation coefficient of 0.46 (95% CI, 0.33-0.58).

CONCLUSION

Preoperative TVS determines accurately rectosigmoid DE lesion length. TVS can thereby contribute to optimal planning of surgical treatment options in women with rectosigmoid DE. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Possible therapeutic effect of royal jelly on endometriotic lesion size, pain sensitivity, and neurotrophic factors in a rat model of endometriosis

Endometriosis is the abnormal growth of endometrial tissue. The goals of the study are: (1) Is any correlation between endometriosis pain and neurotrophins in the serum, dorsal root ganglion (DRG), and peritoneal fluid (PF) in rat models of experimental endometriosis?, (2) Possible therapeutic effects of royal jelly (RJ) on pain scores, size of endometriotic lesion, and neurotrophic factors. Forty-eight Sprague Dawley female rats weighing 205.023 ± 21.54 g were maintained in a standard condition. The rats were randomly divided into one of the six groups: Control (no intervention), Sham-1 (remove of uterine horn), RJ (administration of 200 mg/kg/day RJ for 21 days), Endometriosis (induction of endometriosis), Treatment (induction of endometriosis+administration of 200 mg/kg/day RJ for 21 days), and Sham-2 (induction of endometriosis+administration of water). Formalin test performed for pain evaluation. The levels of Brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), substance P, and calcitonin gene-related peptide (CGRP) were measured by enzyme-linked immunosorbent assay. The mean pain scores in all three phases of the formalin test were significantly increased by endometriosis induction (p < 0.05). The concentrations of BDNF, NGF, and CGRP in DRG of the endometriosis group were significantly higher than these factors in the Control, Sham-1, and RJ groups (p < 0.05). RJ could significantly (p < 0.001) decrease the mean lesion size and the mean pain score in the late phase (p < 0.05). The present results determine that endometriosis pain may be related to nervous system neurotrophic factors. Treatment with RJ could decrease the size of endometriosis lesions as well as pain scores. The findings may shed light on other complementary and alternative remedies for endometriosis.

Characteristics and optimal ablation settings of a novel, contact-force sensing and local impedance-enabled catheter in an ex vivo perfused swine ventricle model

BACKGROUND

Local impedance (LI) has emerged as a new technology that informs on electrical catheter-tissue coupling during radiofrequency (RF) ablation. Recently, IntellaNav StablePoint, a novel LI-enabled catheter that equips contact force (CF) sensing, has been introduced. Although StablePoint and its predecessor IntellaNav MiFi OI share the common technology that reports LI, distinct mechanics for LI sensing between the two products raise a concern that the LI-RF lesion formation relationship may differ.

METHODS

In an ex vivo swine cardiac tissue model, we investigated the initial level and range of a reduction in LI during a 60-s RF ablation and the resultant lesion characteristics at nine combinations of three energy power (30, 40, and 50 W) and CF (10, 30, and 50 g) steps. Correlations and interactions between CF, LI, wattage, and formed lesions were analyzed. Incidence of achieving LI drop plateau and that of a steam pop were also determined.

RESULTS

Positive correlations existed between CF and initial LI, CF and absolute/relative LI drop, CF and lesion volume, and LI drop and lesion volume. At the same LI drop, wattage-dependent gain in lesion volume was observed. Steam pops occurred in all CF steps and the prevalence was highest at 50 W. LI drop predicted a steam pop with a cutoff value at 89Ω.

CONCLUSION

In StablePoint, wattage crucially affects LI drop and lesion volume. Because 30 W ablation may by underpowered for intramural lesion formation and 50 W often resulted in a steam pop, 40 W appears to achieve the balance between the safety and efficacy.

Surgical delays of less than 1 year in Mohs surgery associated with tumor growth in moderately- and poorly-differentiated squamous cell carcinomas but not lower-grade squamous cell carcinomas or basal cell carcinomas: A retrospective analysis

BACKGROUND

Evidence is controversial and limited concerning whether surgical delays are associated with tumor growth for cutaneous squamous cell carcinomas (SCCs) and basal cell carcinomas.

OBJECTIVE

Identify tumor subpopulations that may demonstrate an association between tumor growth and surgical delay.

METHODS

We retrospectively analyzed 299 SCCs and 802 basal cell carcinomas treated with Mohs surgery at a single institution. Time interval from biopsy to surgery represented surgical delay. Change in major diameter (ΔMD) from size at biopsy to postoperative defect represented tumor growth. Independent predictors of ΔMD were identified by multivariate analysis. Linear regression was then utilized to assess for whether the ΔMD from these independent predictors trended with surgical delay.

RESULTS

Surgical delays ranged from 0 to 331 days. Among SCCs, histologic subtype and prior treatment were identified as independent predictors of ΔMD. Significant associations between ΔMD and surgical delay were found for poorly- and moderately-differentiated SCCs, demonstrating growth rates of 0.28 cm and 0.24 cm per month of delay, respectively. The ΔMD for SCCs with prior treatment and basal cell carcinoma subgroups did not vary with surgical delay.

LIMITATIONS

Retrospective design, single center.

CONCLUSION

Surgical delays of less than a year were associated with tumor growth for higher-grade SCCs, with effect sizes bearing potential for clinical significance.

The optimal ablation setting for a local impedance guided catheter in an in vitro experimental model

BACKGROUND

The local impedance (LI) reflects the electrical catheter-tissue coupling and correlates with the local tissue temperature. However, there have been few clinical studies showing the recommended method for LI monitoring catheters. This study aimed to investigate the optimal ablation setting for this catheter in an in vitro experimental model.

METHODS

LI monitoring catheters were used in an excised swine heart experimental model. The tissue contact force (CF) was directly monitored from an external weight scale. Radiofrequency ablation was performed with a combination of various energy power settings (30, 40, and 50 W), and various CFs (10, 30, and 50 g) for 60 s. The correlation between the LI-related indexes, power, and CF with the lesion formation was statistically analyzed.

RESULTS

A positive correlation between the LI or lesion formation and CF was observed under all powers. Although the LI drop always correlated with the maximum lesion depth, lesion diameter, and lesion volume, the coefficient of the correlation value was lower under a high CF (lesion depth, diameter, and volume; 10 g, r = 0.8064, r = 0.8389, r = 0.8477; 30 g, r = 0.7590, r = 0.8063, r = 0.8060; 50 g r = 0.5555, r = 0.5701, and r = 0.5678, respectively). Steam pops occurred only under a 50 W ablation and the LI drop cutoff value for steam pops was 46 Ω.

CONCLUSION

The same LI drop did not always lead to the same lesion size when the CF differed. Monitoring the LI and not exceeding 46 Ω would be useful for a safe ablation.

RF electrode-tissue coverage significantly influences steam pop incidence and lesion size

BACKGROUND

Steam pops are a rare complication associated with radiofrequency (RF) ablation and are hard to predict. The aim of this study was to assess the influence of coverage between the RF ablation electrode and cardiac tissue on steam pop incidence and lesion size.

METHODS AND RESULTS

An ex vivo model using porcine cardiac preparations and contact force sensing catheters was designed to perform RF ablations at different coverage levels between the RF electrode and cardiac tissue. During coverage level I, only the distal part of the ablation electrode was in contact with tissue. During coverage level II half of the ablation electrode, and during coverage level III the entire ablation electrode was embedded in tissue. RF applications (n = 60) at different coverage levels I-III were systematically performed using the same standardized ablation protocol. Ablations during coverage level III resulted in a significantly higher rate of steam pops (100%) when compared to ablations during coverage level II (10%) and coverage level I (0%), log rank p < .001. Coverage level I ablations resulted in significantly smaller lesion depths, diameters, and impedance drops when compared to higher coverage level ablations, p < .001. In the controlled ex vivo model, there was no difference in applied contact force or energy between different coverage levels.

CONCLUSIONS

The level of coverage between RF electrode, cardiac tissue, and the surrounding fluid significantly influenced the incidence of steam pops in an ex vivo setup. Larger coverage between RF electrode and tissue resulted in significantly larger lesion dimensions.

Non-verbal Intelligence in Unilateral Perinatal Stroke Patients With and Without Epilepsies

Background: The risk factors for impaired cognitive development after unilateral perinatal stroke are poorly understood. Non-verbal intelligence seems to be at particular risk, since language can shift to the right hemisphere and may thereby reduce the capacity of the right hemisphere for its originary functions. Pharmaco-refractory epilepsies, a frequent complication of perinatal strokes, often lead to impaired intelligence. Yet, the role of well-controlled epilepsies is less well-understood. Here, we investigated whether well-controlled epilepsies, motor impairment, lesion size, lesion side, and lateralization of language functions influence non-verbal functions. Methods: We recruited 8 patients with well-controlled epilepsies (9-26 years), 15 patients without epilepsies (8-23 years), and 23 healthy controls (8-27 years). All underwent the Test of Non-verbal Intelligence, a motor-independent test, which excludes biased results due to motor impairment. Language lateralization was determined with functional MRI, lesion size with MRI-based volumetry, and hand motor impairment with the Jebson-Taylor Hand Function-Test. Results: Patients with epilepsies showed significantly impaired non-verbal intelligence [Md = 89.5, interquartile range (IQR) = 13.5] compared with controls (Md = 103, IQR = 17). In contrast, patients without epilepsies (Md = 97, IQR = 15.0) performed within the range of typically developing children. A multiple regression analysis revealed only epilepsy as a significant risk factor for impaired non-verbal functions. Conclusion: In patients with unilateral perinatal strokes without epilepsies, the neuroplastic potential of one healthy hemisphere is able to support the development of normal non-verbal cognitive abilities, regardless of lesion size, lesion side, or language lateralization. In contrast, epilepsy substantially reduces this neuroplastic potential; even seizure-free patients exhibit below-average non-verbal cognitive functions.

Germ-free housing conditions do not affect aortic root and aortic arch lesion size of late atherosclerotic low-density lipoprotein receptor-deficient mice

The microbiota has been linked to the development of atherosclerosis, but the functional impact of these resident bacteria on the lesion size and cellular composition of atherosclerotic plaques in the aorta has never been experimentally addressed with the germ-free low-density lipoprotein receptor-deficient (Ldlr^-/- ) mouse atherosclerosis model. Here, we report that 16 weeks of high-fat diet (HFD) feeding of hypercholesterolemic Ldlr^-/- mice at germ-free (GF) housing conditions did not impact relative aortic root plaque size, macrophage content, and necrotic core area. Likewise, we did not find changes in the relative aortic arch lesion size. However, late atherosclerotic GF Ldlr^-/- mice had altered inflammatory plasma protein markers and reduced smooth muscle cell content in their atherosclerotic root plaques relative to CONV-R Ldlr^-/- mice. Neither absolute nor relative aortic root or aortic arch plaque size correlated with age. Our analyses on GF Ldlr^-/- mice did not reveal a significant contribution of the microbiota in late aortic atherosclerosis.

A Semiquantitative Non-invasive Measurement of PcomA Patency in C57BL/6 Mice Explains Variance in Ischemic Brain Damage in Filament MCAo

Numerous studies on experimental ischemic stroke use the filament middle cerebral artery occlusion (fMCAo) model in C57BL/6 mice, but lesion sizes in this strain are highly variable. A known contributor is variation in the posterior communicating artery (PcomA) patency. We therefore aimed to provide a semiquantitative non-invasive in vivo method to routinely assess PcomA patency. We included 43 male C57BL/6 mice from four independent studies using a transient 45 min fMCAo model. Edema-corrected lesion sizes were measured by magnetic resonance (MR) imaging 24 h after reperfusion. Time-of-flight MR angiography was performed 7 days before and 24 h after fMCAo. Scores of PcomA size measured 24 h after, but not scores measured 7 days before fMCAo were negatively correlated with lesion size. Variability in PcomA patency explained 30% of the variance in our cohort (p < 0.0001, coefficient of determination r² = 0.3). In a simulation using parameters typical for experimental stroke research, the power to detect a true effect of d = 1 between two groups increased by 15% when an according covariate was included in the statistical model. We have demonstrated that in vivo measurement of PcomA size is feasible and can lead to increased accuracy in assessing the effect of treatments.

Computer simulation study on the effect of electrode-tissue contact force on thermal lesion size in cardiac radiofrequency ablation

Purpose: In cardiac radiofrequency (RF) ablation, RF energy is often used to create a series of transmural lesions for blocking accessory conduction pathways. Electrode-tissue contact force (CF) is one of the key determinants of lesion formation during RF ablation. Low electrode-tissue CF is associated with ineffective RF lesion formation, whereas excessive CF may increase the risk of steam pop and perforation. By using finite element analysis, we studied lesion size and features at different values of electrode-tissue CF in cardiac RF ablation.Materials and methods: A computer-model-coupled electrode-tissue CF field, RF electric field, and thermal field were developed to study temperature distribution and lesion dimensions in cardiac tissue subjected to CF of 2, 5, 10, 20, 30, and 40 g with identical RF voltage and duration.Results: Increasing CF was associated with an increase in lesion depth, width, and cross-section area. The lesion cross-section area exhibited a linear increase, and the lesion width was significantly greater than lesion depth under the identical ablation condition. The relationship between CF value and lesion size is a power function: Lesion Size = a × CF^b (Lesion Depth = 3.17 × CF^0.14 and Lesion Width = 5.17 × CF^0.14).Conclusions: This study confirmed that CF is a major determinant of RF lesion size and that electrode-tissue CF affects the amount of power dissipated in tissue. At a constant RF voltage and application time, RF lesion size increases as CF increases.

Poststroke Impairment and Recovery Are Predicted by Task-Specific Regionalization of Injury

Lesion size and location affect the magnitude of impairment and recovery following stroke, but the precise relationship between these variables and functional outcome is unknown. Herein, we systematically varied the size of strokes in motor cortex and surrounding regions to assess effects on impairment and recovery of function. Female Sprague Dawley rats (N = 64) were evaluated for skilled reaching, spontaneous limb use, and limb placement over a 7 week period after stroke. Exploration and reaching were also tested in a free ranging, more naturalistic, environment. MRI voxel-based analysis of injury volume and its likelihood of including the caudal forelimb area (CFA), rostral forelimb area (RFA), hindlimb (HL) cortex (based on intracranial microstimulation), or their bordering regions were related to both impairment and recovery. Severity of impairment on each task was best predicted by injury in unique regions: impaired reaching, by damage in voxels encompassing CFA/RFA; hindlimb placement, by damage in HL; and spontaneous forelimb use, by damage in CFA. An entirely different set of voxels predicted recovery of function: damage lateral to RFA reduced recovery of reaching, damage medial to HL reduced recovery of hindlimb placing, and damage lateral to CFA reduced recovery of spontaneous limb use. Precise lesion location is an important, but heretofore relatively neglected, prognostic factor in both preclinical and clinical stroke studies, especially those using region-specific therapies, such as transcranial magnetic stimulation.SIGNIFICANCE STATEMENT By estimating lesion location relative to cortical motor representations, we established the relationship between individualized lesion location, and functional impairment and recovery in reaching/grasping, spontaneous limb use, and hindlimb placement during walking. We confirmed that stroke results in impairments to specific motor domains linked to the damaged cortical subregion and that damage encroaching on adjacent regions reduces the ability to recover from initial lesion-induced impairments. Each motor domain encompasses unique brain regions that are most associated with recovery and likely represent targets where beneficial reorganization is taking place. Future clinical trials should use individualized therapies (e.g., transcranial magnetic stimulation, intracerebral stem/progenitor cells) that consider precise lesion location and the specific functional impairments of each subject since these variables can markedly affect therapeutic efficacy.

Effect of metastatic lesion size and location on the load-bearing capacity of vertebrae using an optimized ash density-modulus equation

About 1.8 million new cancer cases are estimated in the US in 2019 from which 50-85% might metastasize to the thoracic and lumbar spines. Subject-specific quantitative computed tomography-based finite element analysis (QCT/FEA) is a promising used tool to predict vertebral fracture properties. The aims of this study were twofold: First, to develop an optimized equation for the elastic modulus accounting for all input parameters in FE modeling of fracture properties. Second, to assess the effect of lesion size and location on the predicted fracture loads. An inverse QCT/FEA method was implemented to determine optimal coefficients for the modulus equation as a function of ash density. Lesions of 16 and 20 mm were then virtually located at the center, off-centered, anterior, and posterior regions of the vertebrae. A total of 6426 QCT/FEA models were run to optimize the coefficients and evaluate the effect of lesions on fracture properties. QCT/FEA predicted stiffness showed high correlations (50%) with the experimentally measured values. Compared to a 16 mm lesion size, a 20 mm lesion had a reduction in failure load of 55%, 57%, 52%, and 44% at the center, off-centered, anterior cortex, and pedicle, respectively (p < 0.001). Lesions affecting mostly trabecular bone showed the largest reduction in predicted failure loads (about 55%), and females presented weaker outcomes than males. An optimal elastic modulus equation resulted in accurate vertebral stiffness predictions. A deterioration of the trabecular bone due to the presence of a lesion highly affected the predicted fracture loads, and this reduction was significantly higher in females compared to males.

Long-term outcomes of patients with gastric adenoma in Korea: A retrospective observational study

New endoscopic resection techniques are constantly being developed for gastric adenoma, which can be classified as low or high grade according to the Vienna classification. However, long-term data on gastric adenoma (e.g., removal or follow-up after resection via endoscopy) remain lacking.We retrospectively analyzed 133 cases with gastric adenoma that underwent endoscopic resection from January 2010 to November 2018. We analyzed the risk factors and frequency of patients with synchronous and metachronous lesions after endoscopic resection for gastric adenoma and followed them for more than 2 years.One hundred six (79.7%) and 27 patients (20.3%) received endoscopic resection (ER) once and more than twice, respectively. Compared with the initial endoscopic biopsy pathological results, the upgraded and downgraded histological discrepancy rates were 10.5% (n = 14) and 3.0% (n = 4) after resection, respectively. The mean time to synchronous/metachronous recurrence was 2.23 years. The average lesion size at first procedure was larger in the multiple ER group than in the single ER group (2.00 vs 1.10 cm; P = .040). Eleven (8.3%) and 16 patients (12.0%) had recurred synchronous and metachronous lesions, respectively. In the multivariate Cox analysis of the recurrence group, intestinal metaplasia (hazard ratio, 2.761; 95% confidence interval, 1.117-6.820; P = .028) and lesion size (hazard ratio, 1.607; 95% confidence interval, 1.082-2.385; P = .019) were independent factors for receiving endoscopic resection more than twice.If patients have severe intestinal metaplasia or large size of lesion at endoscopic resection for gastric adenoma, periodic observation is necessary.

Dose and blending fraction quantification for adaptive statistical iterative reconstruction based on low-contrast detectability in abdomen CT

Purpose

The utilization of iterative reconstruction makes it difficult to identify the dose‐noise relationship, resulting in empirical design of scan protocols and inconsistent conclusions on dose reduction for consistent image quality. This study was to quantitatively determine the dose and the blending fraction of adaptive statistical iterative reconstruction (ASIR) based on the specified low‐contrast detectability (LCD).

Methods

A tissue equivalent abdomen phantom and a GE discovery 750 HD computed tomography (CT) were utilized. The normality of the noise distribution was tested at various spatial scales (2.1–9.8 mm) in the presence of ASIR (10–100%) with a wide range of doses (2.24–38 mGy). The statically defined minimum detectable contrast (MDC) was used as the image quality metric. The parametric model decomposed the MDC into two terms: one with and the other without ASIR, each was related to the dose in the form of power law with factors and indices dependent on spatial scales. The parameters were identified by least‐square fitting to the experimental data. By considering the constraint of the blending fraction in the range of [0, 1], the dose and ASIR blending fraction were determined for any specified low‐contrast detectability (LCD), quantified by the MDC at the concerned lesion size.

Results

It was verified that noise distribution is normal in the presence of ASIR. It was also found that the noises obtained from the subtractions of adjacent slices had an underestimate of 20% as compared to the ground truth noises, regardless of the spatial scale, pitch, or ASIR blending fraction. The least‐square fitting for the parametric model resulted in correlation coefficients from 0.905 to 0.996. The root‐mean‐square errors ranged from 1.27% to 7.15%.

Conclusion

The parametric model can be used to form a look‐up‐table for dose and ASIR blending fraction. The dose choices may be substantially limited in some cases depending on the required LCD.

Relationship between the ablation index, lesion formation, and incidence of steam pops

BACKGROUND

The ablation index (AI) is reported to be useful for a durable pulmonary vein isolation (PVI). However, there have been no studies investigating the relationship between the power, contact force (CF), AI, and steam pops.

METHODS

Using an in vitro model, ablation energy was delivered until a steam pop occurred and the time to the steam pop and AI when the steam pop occurred were measured. The experiment was performed with a combination of various powers (20, 30, 40, and 50 W) and contact forces (CFs) (10, 30, and 50 g) 20 times for each setting. The analysis consisted of two protocols. The first protocol was a comparison between the ablation power and several parameters under the same CF (10, 30, and 50 g). The second protocol was a comparison between the CF and several parameters under the same power (20, 30, 40, and 50 W). The correlation between the lesion formation and ablation parameters was evaluated.

RESULTS

The AI value when steam pops occurred varied depending on the ablation settings. All AI median values were <500 under an ablation power of 50 W. On other hand, the median ablation time up to the steam pop was more than 46 seconds, but all median values of the AI were more than 550 under an ablation with 20 W.

CONCLUSIONS

The AI cannot predict steam pops. A low power and long duration ablation could obtain a high AI value. However, high-power ablation could not obtain a high AI value because of an early occurrence of steam pops.

Three-dimensional computed tomography measurement accuracy of varying Hill-Sachs lesion size

BACKGROUND

The glenoid track concept has been proposed to correlate shoulder stability with bone loss. Accurate assessment of Hill-Sachs lesion size preoperatively may affect surgical planning and postoperative outcomes; however, no measurement method has been universally accepted. This study aimed to assess the accuracy and reliability of measuring Hill-Sachs lesion sizes using 3-dimensional (3D) computed tomography (CT).

METHODS

Nine polyurethane humerus bone substitutes were used to create Hill-Sachs lesions of varying sizes with a combination of lesion depth (shallow, intermediate, and deep) and width (small, medium, and large). Specimens were scanned with a clinical CT scanner for size measurements and a micro-CT scanner for measurement of true lesion size. Six evaluators repeated measurements twice in a 2-week interval. Scans were measured by use of 3D CT reconstructions for length, width, and Hill-Sachs interval and with use of 2D CT for depth. The interclass correlation coefficient evaluated interobserver and intraobserver variability and percentage error, and Student t-tests assessed measurement accuracy.

RESULTS

Interclass correlation coefficient reliability demonstrated strong agreement for all variables measured (0.856-0.975). Percentage error between measured length and measured depth and the true measurement significantly varied with respect to both lesion depth (P = .003 and P = .005, respectively) and lesion size (P = .049 and P = .004, respectively).

DISCUSSION AND CONCLUSIONS

The 3D CT imaging is effective and reproducible in determining lesion size. Determination of Hill-Sachs interval width is also reliable when it is applied to the glenoid track concept. Measured values on 3D and 2-dimensional imaging using a conventional CT scanner may slightly underestimate true measurements.

Lesion Size Is a Predictor of Clinical Outcomes After Bone Marrow Stimulation for Osteochondral Lesions of the Talus: A Systematic Review

BACKGROUND

The critical lesion size treated with bone marrow stimulation (BMS) for osteochondral lesions of the talus (OLTs) has been 150 mm² in area or 15 mm in diameter. However, recent investigations have failed to detect a significant correlation between the lesion size and clinical outcomes after BMS for OLTs.

PURPOSE

To systematically review clinical studies reporting both the lesion size and clinical outcomes after BMS for OLTs.

STUDY DESIGN

Systematic review.

METHODS

A systematic search of the MEDLINE and EMBASE databases was performed in March 2015 based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Included studies were evaluated with regard to the level of evidence (LOE), quality of evidence (QOE), lesion size, and clinical outcomes.

RESULTS

Twenty-five studies with 1868 ankles were included; 88% were either LOE 3 or 4, and 96% did not have good QOE. The mean area was 103.8 ± 10.2 mm² in 20 studies, and the mean diameter was 10.0 ± 3.2 mm in 5 studies. The mean American Orthopaedic Foot and Ankle Society score improved from 62.4 ± 7.9 preoperatively to 83.9 ± 9.2 at a mean 54.1-month follow-up in 14 studies reporting both preoperative and postoperative scores with a mean follow-up of more than 2 years. A significant correlation was found in 3 studies, with a mean lesion area of 107.4 ± 10.4 mm², while none was reported in 8 studies, with a mean lesion area of 85.3 ± 9.2 mm². The lesion diameter significantly correlated with clinical outcomes in 2 studies (mean diameter, 10.2 ± 3.2 mm), whereas none was found in 2 studies (mean diameter, 8.8 ± 0.0 mm). However, the reported lesion size measurement method and evaluation method of clinical outcomes widely varied among the studies.

CONCLUSION

An assessment of the currently available data does suggest that BMS may best be reserved for OLT sizes less than 107.4 mm² in area and/or 10.2 mm in diameter. Future development in legitimate prognostic size guidelines based on high-quality evidence that correlate with outcomes will surely provide patients with the best potential for successful long-term outcomes.

Risk of persistent and recurrent cervical neoplasia following incidentally detected adenocarcinoma in situ

BACKGROUND

Adenocarcinoma in situ of the uterine cervix is a precursor to cervical adenocarcinoma and may coexist with both adenocarcinoma and high-grade squamous dysplasia (cervical intraepithelial neoplasia 2 and 3). Up to 60% of adenocarcinoma in situ lesions are detected incidentally following excisional biopsies performed for the treatment of cervical intraepithelial neoplasia 2/3. To date there are no data regarding risk factors for persisting or progressive cervical neoplasia in these patients.

OBJECTIVE

We sought to investigate patient outcomes following incidentally detected cervical adenocarcinoma in situ after loop electrosurgical excision procedure or cold knife cone biopsy performed for the treatment of high-grade cervical intraepithelial neoplasia.

STUDY DESIGN

We conducted a retrospective, population-based cohort study of Western Australian patients with an incidental diagnosis of adenocarcinoma in situ from 2001 through 2012. Primary outcomes were persistent or recurrent cervical intraepithelial neoplasia 2/3 and or adenocarcinoma in situ, and invasive adenocarcinoma during follow-up (<12 months) and surveillance (≥12 months) periods.

RESULTS

The cohort comprised 298 patients, with 228 (76.5%) treated initially by loop electrosurgical excision procedure and 70 (23.5%) treated by cold knife cone biopsy. The mean age was 31.2 (range 18-68) years and the median length of follow-up was 2.4 (range 0.3-12.2) years. Overall, 11 (3.7%) patients had cervical intraepithelial neoplasia 2/3, 23 (7.7%) had adenocarcinoma in situ, and 3 (1.0%) had adenocarcinoma diagnosed during the follow-up and surveillance periods. Age >30 years, pure adenocarcinoma in situ lesions, and larger lesions (>8 mm) were associated with a greater risk of disease persistence or recurrence.

CONCLUSION

Following the incidental detection of adenocarcinoma in situ, age >30 years, pure adenocarcinoma in situ lesions, and lesions >8 mm were significantly associated with disease persistence/recurrence. In younger women, incidentally detected adenocarcinoma in situ that coexists with cervical intraepithelial neoplasia 2/3 and is <8 mm extent with clear margins may not require reexcision.

Consistent low-contrast detectability for variable patient sizes and corresponding dose in abdominal CT

PURPOSE

For CT dose optimization, one needs to address two important questions. The first is how various lesion-specific detection tasks demand different patient doses for the same patient. The second is how the variation of the patient size requires different patient doses for the same lesion detection task. In this study, we attempted to find quantitative solutions to these questions by utilizing a wide range of abdomen phantoms.

METHODS

A simplified model with a monochromatic fan beam passing through a bowtie-filter and an elliptical object was proposed. The model relates the minimum detectable contrast (MDC) to the size-specific dose by power index of -1/2 and to the lesion size by power index of -1 with a patient size dependence function (PSDF) as the proportionality factor. The experimental validation was performed using seven abdomen phantoms (lateral ranges: 10 cm-39 cm) scanned with helical modes at various dose levels on two 64-slice scanners (Siemens mCT and GE HD 750). Noise images were obtained using subtractions among adjacent slices in the images reconstructed with filtered backprojection. It was verified that the mean pixel value distributions from various small regions (1.8 mm-10 mm) are Gaussian, thus the concept of the statistically defined minimum detectable contrast (SD-MDC), defined as distribution's standard deviation multiplied by 3.29, can be applied. The impact of the helical pitch and the high-definition (HD) acquisition was also studied.

RESULTS

The experimental data from all phantoms were found to fit the power law well (R²  ≥ 0.983). The PSDF was found to be scanner dependent - modeled with a Gaussian amplifier (R²  = 0.983) for one manufacturer and with an exponential function for the other (R²  = 0.990). The MDC relationship was not found to be impacted by different pitches or by HD acquisition. The results were used to find the size-specific doses and corresponding acquisition techniques required by consistent low-contrast detectability for variable patient sizes. Visual comparisons on the low-contrast insert images demonstrated that the derived techniques delivered consistent low-contrast detectability.

CONCLUSIONS

We have modeled and verified the relationship of the minimum detectable contrast to the patient size, the patient dose, and the lesion size from the images reconstructed with filtered backprojection. The findings can be useful for task-specific dose modulation on abdomen CT studies.

Improvement of Lesion Detection by Complete Angular Compound Ultrasonic Elastography

Quasi-static ultrasound elastography is an emerging diagnostic imaging modality for determining the stiffness of pathologically changed soft tissues, which do not show significant differences in acoustic impedance for B-mode imaging. Although some methods were applied to improve the signal-to-noise ratio (SNRe) and contrast-to-noise ratio (CNRe) of the constructed elastogram, nonuniform strain distribution at the internal boundary of a hard inclusion, even with the uniform displacement on the surface, is an inherent mechanical effect and results in distortion at the detected lesion boundary. To overcome such stress concentrations, a new elastographic modality was proposed, where the elastograms from different angles throughout 360° were compounded. The strain field and subsequent ultrasound images were calculated using the finite element method (FEM) and Field II, respectively, from which the elastograms were constructed. The performance of complete angular compound elastography with varied interval angles, lesion sizes, and ratios of Young's moduli of the lesion to the background was simulated and compared with that of conventional axial strain elastography. It is found that viewing the lesion from only about 10 angles (interval of 36°) would significantly improve the image quality of elastogram (increasing SNRe by at least 13% and CNRe by at least 5.8 dB), reduce the lesion distortion in the lateral direction, and enhance the sensitivity, resolution, and accuracy of lesion detection. A preliminary phantom study showed similar improvements. Altogether, complete angular compound elastography improves the elastogram quality and reduces the mechanical effects in lesion detection.

Small lesion size measured by colposcopy may predict absence of cervical intraepithelial neoplasia in a large loop excision of the transformation zone specimen

OBJECTIVE

To evaluate whether colposcopic measurement of the lesion size at diagnosis and/or human papillomavirus (HPV) genotyping can predict the absence of dysplasia in a large loop excision of the transformation zone (LLETZ) specimen in women treated for squamous intraepithelial lesions/cervical intraepithelial neoplasia (SIL/CIN).

DESIGN

Prospective observational study.

SETTING

Tertiary university hospital.

POPULATION

A cohort of 116 women who underwent LLETZ because of biopsy-proven low-grade SIL/CIN that had persisted for 2 years, or because of a high-grade SIL/CIN diagnosed in the referral visit and squamocolumnar junction completely visible (types 1 or 2, according to the International Federation of Cervical Pathology and Colposcopy, IFCPC).

METHODS

After LLETZ the women were classified by histology into the study group (absence of SIL/CIN in the surgical specimen, 28/116, 24.1%) and the control group (SIL/CIN in the LLETZ specimen, 88/116, 75.9%).

MAIN OUTCOME MEASURES

The size of the lesion determined in the diagnostic colposcopy and the HPV genotype were evaluated in all women.

RESULTS

The lesion size was significantly smaller in the study group (25.7 ± 37.8 versus 84.5 ± 81.7 mm² ; P < 0.001). A lesion size of ≤12 mm² and HPV types other than 16 or 18 were associated with an absence of SIL/CIN in the LLETZ specimen (P < 0.001 and P = 0.016, respectively). On multivariate analysis only a lesion size of ≤12 mm² predicted the absence of SIL/CIN (odds ratio, OR 10.6; 95% confidence interval, 95% CI 3.6-30.6; P < 0.001). A lesion size of ≤12 mm² had a specificity of 90.9% (95% CI 83.0-95.3%) and a negative predictive value of 86.0% (95% CI 77.5-91.6%) to predict the absence of SIL/CIN in the surgical specimen.

CONCLUSIONS

Small lesion size in diagnostic colposcopy could predict the absence of SIL/CIN in the LLETZ specimen. Colposcopy measurement of lesion size prior to LLETZ may avoid unnecessary treatment.

TWEETABLE ABSTRACT

Small lesion size in colposcopic evaluation might predict the absence of SIL/CIN in an LLETZ specimen.

The Effect of Lesion Size on the Organization of the Ipsilesional and Contralesional Motor Cortex

Recovery of hand function following lesions in the primary motor cortex (M1) is associated with a reorganization of premotor areas in the ipsilesional hemisphere, and this reorganization depends on the size of the lesion. It is not clear how lesion size affects motor representations in the contralesional hemisphere and how the effects in the 2 hemispheres compare. Our goal was to study how lesion size affects motor representations in the ipsilesional and contralesional hemispheres. In rats, we induced lesions of different sizes in the caudal forelimb area (CFA), the equivalent of M1. The effective lesion volume in each animal was quantified histologically. Behavioral recovery was evaluated with the Montoya Staircase task for 28 days after the lesion. Then, the organization of the CFA and the rostral forelimb area (RFA)—the putative premotor area in rats—in the 2 cerebral hemispheres was studied with intracortical microstimulation mapping techniques. The distal forelimb representation in the RFA of both the ipsilesional and contralesional hemispheres was positively correlated with the size of the lesion. In contrast, lesion size had no effect on the contralesional CFA, and there was no relationship between movement representations in the 2 hemispheres. Finally, only the contralesional RFA was negatively correlated with chronic motor deficits of the paretic forelimb. Our data show that lesion size has comparable effects on motor representations in premotor areas of both hemispheres and suggest that the contralesional premotor cortex may play a greater role in the recovery of the paretic forelimb following large lesions.

Carbon nanotube facilitation of myocardial ablation with radiofrequency energy

BACKGROUND

The use of carbon nanotubes (CNTs) in oncology has been proposed for the purpose of sensitizing tumors to radiofrequency (RF) ablation. We hypothesize that myocardial tissue infiltrated with CNTs will improve thermal conductivity of RF heating and lead to altered ablation lesion characteristics.

METHODS

An ex vivo model consisting of viable bovine myocardium, a circulating saline bath at 37 °C, a submersible load cell, and a deflectable sheath was assembled. A 4-mm nonirrigated ablation catheter was positioned with 10 gm of force over bovine myocardium infiltrated with CNTs, 0.9% saline, or sham injections. A series of ablation lesions were delivered at 20 and 50 W, and lesion volumes were acquired by analyzing tissue sections with a digital micrometer. Tissue temperature analyses at 3 and 5 mm depths were also performed.

RESULTS

Myocardial tissue treated with CNTs resulted in significantly larger lesions at both low and high power settings. The electrical impedance was increased in CNT treated tissue with a greater impedance change observed in the CNT infiltrated myocardium. The thermal conductivity of heat generated by application of RF in the tissue was altered by the presence of CNTs, resulting in higher temperatures at 3 and 5 mm depths for both 20 and 50 W.

CONCLUSIONS

Myocardial tissue treated with CNTs resulted in significantly larger lesions at both low and high power settings. The electrical and thermal conductivity of heat generated by application of RF in myocardial tissue was altered by the presence of CNTs. Further research is needed to assess the in vivo applicability for this concept of facilitated ablation with CNTs.

Treatment of osteochondral lesions of the talus with particulated juvenile cartilage

BACKGROUND

Numerous modalities are used today to treat symptomatic osteochondral lesions in the ankle. However, there are ongoing challenges with the treatment of certain lesions, and concerns exist regarding long-term effectiveness.

METHODS

The purpose of the study was to collect clinical outcomes of pain and function in retrospectively and prospectively enrolled patients treated with particulated juvenile cartilage for symptomatic osteochondral lesions in the ankle. This study collected outcomes and incidence of reoperations in standard clinic patients. The analysis presented here includes final follow-up to date for 12 males and 11 females representing 24 ankles. Subjects had an average age at surgery of 35.0 years and an average body mass index of 28 ± 5.8. Fourteen ankles had failed at least 1 prior bone marrow stimulation procedure. The average lesion size was 125 ± 75 mm(2), and the average depth was 7 ± 5 mm. In conjunction with the treatment, 9 (38%) ankles had 1 concomitant procedure and 9 (38%) had more than 1 concomitant procedure. Clinical evaluations were performed with an average follow-up of 16.2 months.

RESULTS

Average outcome scores at final follow-up were American Orthopaedic Foot & Ankle Society Ankle-Hindfoot Scale 85 ± 18 with 18 (78%) ankles demonstrating good to excellent scores, Short-Form 12 Health Survey (SF12) physical composite score 46 ± 10, SF12 mental health composite score 55 ± 7.1, Foot and Ankle Ability Measure (FAAM) activities of daily living 82 ± 14, FAAM Sports 63 ± 27, and 100-mm visual analog scale for pain 24 ± 25. Outcomes data divided by lesion size demonstrated 92% (12/13) good to excellent results in lesions 10 mm or larger and those smaller than 15 mm. To date, 1 partial graft delamination has been reported at 16 months.

CONCLUSIONS

Preliminary data from a challenging clinical population with large, symptomatic osteochondral lesions in the ankle suggest that treatment with particulated juvenile cartilage could improve function and decrease pain. Longer follow-up and additional subjects are needed to evaluate improvement level and ideal patient indications.

LEVEL OF EVIDENCE

Level IV, case series.

Osteoarthritis of the knee at 3.0 T: comparison of a quantitative and a semi-quantitative score for the assessment of the extent of cartilage lesion and bone marrow edema pattern in a 24-month longitudinal study

OBJECTIVE

To compare a semi-quantitative and a quantitative morphological score for assessment of early osteoarthritis (OA) evolution.

MATERIALS AND METHODS

3.0 T MRI of the knee was performed in 60 women, 30 with early OA (each 15 with Kellgren-Lawrence grade 2 and 3) and 30 age-matched controls at baseline and at 12 and 24 months. Pathological condition was assessed with the whole-organ magnetic resonance imaging score (WORMS). Cartilage abnormalities and bone marrow edema pattern (BMEP) were also quantified using a previously introduced morphological quantitative score. These data were correlated with changes in clinical parameters and joint space width using generalized estimation equations (GEE).

RESULTS

At baseline, OA patients had significantly (p < 0.05) more and larger cartilage lesions and BMEP. During follow-up, cartilage lesions increased significantly (p < 0.05) in the patients compared with controls: WORMS showed progression only at the lateral patella, whereas the quantitative score revealed progression additionally at the trochlea and at the medial compartment. Both scores showed a significant (p < 0.05) increase in BMEP at the lateral femur in OA patients. In addition, quantitative scores of BMEP of the whole knee decreased significantly (p < 0.05) after 12 months and increased after 24 months in the patients, but showed an increase in controls at all follow-up examinations. Only weak correlations between structural imaging findings and clinical parameters were observed.

CONCLUSION

Quantitative assessment of cartilage lesions and BMEP is more sensitive to changes during the course of the disease than semi-quantitative scoring. However, structural imaging findings do not correlate well with the clinical progression of OA.

Early beneficial effect of matrix metalloproteinase inhibition on blood-brain barrier permeability as measured by magnetic resonance imaging countered by impaired long-term recovery after stroke in rat brain

Proteolytic disruption of the extracellular matrix with opening of the blood-brain barrier (BBB) because of matrix metalloproteinases (MMPs) occurs in reperfusion injury after stroke. Matrix metalloproteinase inhibition blocks the early disruption of the BBB, but the long-term consequences of short-term MMP inhibition are not known. Recently, a method to quantify BBB permeability by graphical methods was described, which provides a way to study both early disruption of the BBB and long-term effects on recovery in the same animal. We used a broad-spectrum MMP inhibitor, BB1101, to determine both the usefulness of the Magnetic resonance imaging (MRI) method for treatment studies and the long-term effects on recovery. Magnetic resonance imaging studies were performed in control (N=6) and drug-treated (N=8) groups on a dedicated 4.7-T MRI scanner. Adult Wistar-Kyoto underwent a 2-h middle cerebral artery occlusion followed by an MRI study after 3 h of reperfusion, which consisted of T2- and diffusion-weighted techniques. Additionally, a rapid T1 mapping protocol was also implemented to acquire one pre-gadolinium-diethylenetriaminepentaacetic acid baseline data set followed by postinjection data sets at 3-min intervals for 45 mins. The same animal was imaged again at 48 h for lesion size estimation. Data was postprocessed pixel-wise to generate apparent diffusion coefficient and permeability coefficient maps. Treatment with BB-1101 significantly reduced BBB permeability at 3 h, but failed to reduce lesion size at 48 h. Behavioral studies showed impairment in recovery in treated rats. Magnetic resonance imaging allowed for the monitoring of multiple parameters in the same animal. Our studies showed that BB-1101 was an excellent inhibitor of the BBB damage. However, results show that BB-1101 may be responsible for significant deterioration in neurologic status of treated animals. Although these preliminary results suggest that BB-1101 is useful in reducing early BBB leakage owing to reperfusion injury in stroke, further studies will be needed to determine whether the later detrimental effects can be eliminated by shorter time course of drug delivery.

Real time quantification of low temperature radiofrequency ablation lesion size using phased array intracardiac echocardiography in the canine model: comparison of two dimensional images with pathological lesion characteristics

OBJECTIVE

To evaluate the feasibility of quantifying low temperature radiofrequency catheter ablation (RFCA) lesions using a phased array intracardiac echocardiography (ICE) catheter--with better tissue penetration and in a deflectable device-in the canine model.

INTERVENTION

Low temperature radiofrequency (RF) energy (50-60 degrees C at up to 40 W) was delivered to the left ventricle in 11 beagles for 60 seconds, using an 8 French catheter with a deflectable tip and a 4 mm distal electrode.

MAIN OUTCOME MEASURES

Comparison of the width and depth of RFCA lesions measured by ICE with pathological findings.

RESULTS

33 RF energies were delivered in 11 dogs. 31 lesions (94%) were confirmed at necropsy. 27 of 31 ablation lesions (87%) were detected by ICE. The mean (SD) width and depth of the ICE detected lesions were 10.4 (2.6) mm and 5.7 (1.9) mm, respectively. Pathological findings showed that RFCA lesions consisted of inner and outer layers. Macroscopically, the mean (SD) width and depth of the inner layers were 7.6 (2.3) mm and 3.6 (1.2) mm and those for the whole layers were 10.0 (2.8) mm and 5.3 (1.5) mm, respectively. Microscopically, the inner and outer layers corresponded to necrotic and oedematous areas, respectively. The ICE detected lesion size had better correlation with the pathological measurements of the whole layers in width (r = 0.911) and in depth (r = 0.756).

CONCLUSION

The real time evaluation of RFCA lesion size using the phased array ICE is feasible, even with a low temperature RF application. However, ICE slightly overestimates RFCA lesion size compared with pathological necrotic lesion size.