Cesarean Scar Pregnancy: Comparing the Efficacy and Tolerability of Treatment with High-Intensity Focused Ultrasound and Uterine Artery Embolization

Treatments for cesarean scar pregnancy: a systematic review and meta-analysis

OBJECTIVE

To report the outcome of cesarean scar pregnancy (CSP) undergoing treatment.

METHODS

MEDLINE, Embase and CINAHL databases were searched. Inclusion criteria were women with CSP undergoing treatment. The primary outcome was successful treatment for CSP, defined as no need for additional medical or surgical strategies. Secondary outcomes were the type of additional treatment (surgical or medical), need for blood transfusion, emergency laparotomy, hysterectomy, post-treatment complications.All these outcomes were explored in women undergoing single and compound treatments for CSP. Furthermore, we performed a separate sub-group analysis only including studies which reported on the outcomes of elective treatments. Random effects meta-analyses were used to analyze the data and results reported as pooled proportions or odd ratio (OR).

RESULTS

176 studies (13431 women with CSP undergoing treatment) were included.Successful treatment after primary intervention was achieved in 86.2% (95% CI 82.3-89.7) of women with CSP undergoing treatment with ultrasound guided suction curettage, 72.4% (95% CI 64.8-79.3) with systemic MTX, 81.6% (95% CI 72.3-89.3) with local MTX, 83.9% (95% CI 66.7-95.6) with interventional radiology, 90.42% (95% CI 82.9-96.0) with hysteroscopy, 96.1% (95% CI (92.3-98.6) with laparoscopy and 92.6 with high intensity focused ultrasound (95% CI 78.2-99.6). Post-treatments complications were reported in 3.5% (95% CI 1.7-6.0) of women treated with systemic MTX, 5.9% (95% CI 0.8-15.1) with local MTX or KCl, 1.2% (95% CI 0.1-3.5) with interventional radiology, 1.4% (95% CI 0.4-2.9) with hysteroscopy, 5.5% (95% CI 0.4-25.7) with high intensity focused ultrasound and in none of the cases treated with ultrasound guided suction curettage.When considering compound treatments, successful resolution of CSP was achieved in 91.9% (95% CI 88.0-95.10) of women treated with interventional radiology followed by curettage, 83.3% (95% CI 68.8-93.8) with systemic MTX and curettage, 79.4% (95% CI 56.3-95.2) with local MTX and curettage, 96.2% (95% CI 92.3-98.7) with curettage followed by single or double balloon insertion in the uterine cavity, 98.3% (95% CI 95.9-99.7) with high intensity focused ultrasound followed by curettage, 91.1% (95% CI 3.4-97.0) with interventional radiology followed by removal of CSP with hysteroscopy, 64.3% (95% CI 13.8-99.2) with interventional radiology and systemic MTX and in 95.5% (95% CI 92.9-97.5) with curettage and hysteroscopy.When considering studies reporting a comparison between different treatments, there was no difference between systemic vs local MTX in the primary outcome. Curettage was associated with a higher chance of achieving a successful treatment.

CONCLUSIONS

A multitude of treatments for CSP have been reported in the published literature. All treatments described for CSP are apparently equally effective in treating this condition. The findings from this systematic review highlight the need for adopting a common definition and outcome reporting of CSP to better elucidate its natural history, estimate the magnitude of maternal complication after treatment and design appropriately powered RCT to elucidate the optimal treatment of CSP according to its ultrasound phenotype and gestational age at treatment, in terms of effective resolution of the condition and risk of post-intervention complications.

Efficacy and safety of treatment modalities for cesarean scar pregnancy: a systematic review and network meta-analysis

OBJECTIVE

Cesarean scar pregnancy may lead to varying degrees of complications. There are many treatment methods for it, but there are no unified or recognized treatment strategies. This systematic review and network meta-analysis aimed to observe the efficacy and safety of treatment modalities for patients with cesarean scar pregnancy.

DATA SOURCES

MEDLINE, Embase, and Cochrane Central Register of Controlled Trials were searched from their inception to January 31, 2024. In addition, relevant reviews and meta-analyses were manually searched for additional references.

STUDY ELIGIBILITY CRITERIA

Our study incorporated head-to-head trials involving a minimum of 10 women diagnosed with cesarean scar pregnancy through ultrasound imaging or magnetic resonance imaging, encompassing a detailed depiction of primary interventions and any supplementary measures. Trials with a Newcastle-Ottawa scale score <4 were excluded because of their low quality.

METHODS

We conducted a random-effects network meta-analysis and review for cesarean scar pregnancy. Group-level data on treatment efficacy and safety, reproductive outcomes, study design, and demographic characteristics were extracted following a predefined protocol. The quality of studies was assessed using the Cochrane risk-of-bias tools for randomized controlled trials and the Newcastle‒Ottawa scale for cohort studies and case series. The main outcomes were efficacy (initial treatment success) and safety (complications), of which summary odds ratios and the surface under the cumulative ranking curve using pairwise and network meta-analysis with random effects.

RESULTS

Seventy-three trials (7 randomized controlled trials) assessing a total of 8369 women and 17 treatment modalities were included. Network meta-analyses were rooted in data from 73 trials that reported success rates and 55 trials that reported complications. The findings indicate that laparoscopy, transvaginal resection, hysteroscopic curettage, and high-intensity focused ultrasound combined with suction curettage demonstrated the highest cure rates, as evidenced by surface under the cumulative ranking curve rankings of 91.2, 88.2, 86.9, and 75.3, respectively. When compared with suction curettage, the odds ratios (95% confidence intervals) for efficacy were as follows: 6.76 (1.99-23.01) for laparoscopy, 5.92 (1.47-23.78) for transvaginal resection, 5.00 (1.99-23.78) for hysteroscopic curettage, and 3.27 (1.08-9.89) for high-intensity focused ultrasound combined with suction curettage. Complications were more likely to occur after receiving uterine artery chemoembolization, suction curettage, methotrexate+hysteroscopic curettage, and systemic methotrexate; hysteroscopic curettage, high-intensity focused ultrasound combined with suction curettage, and Lap were safer than the other options derived from finite evidence; and the confidence intervals of all the data were wide.

CONCLUSION

Our findings indicate that laparoscopy, transvaginal resection, hysteroscopic curettage, and high-intensity focused ultrasound combined with suction curettage procedures exhibit superior efficacy with reduced complications. The utilization of methotrexate (both locally guided injection and systemic administration) as a standalone medical treatment is not recommended.

Efficacy and safety of high-intensity focused ultrasound combined with suction curettage for the treatment of caesarean scar pregnancy: a systematic review and single-arm meta-analysis

PURPOSE

Caesarean scar pregnancy (CSP) presents a significant clinical challenge owing to the associated risks of uterine scar rupture, severe haemorrhage and adverse maternal outcomes. This study aimed to assess the safety and efficacy of combining high-intensity focused ultrasound (HIFU) with suction curettage for treating CSP.

METHODS

We conducted a comprehensive search in four databases, namely PubMed, Web of Science, Embase and Cochrane Library, to identify published studies evaluating the use of HIFU combined with suction curettage to treat CSP. Intraoperative blood loss, treatment success rate, and reproductive results were the primary outcomes assessed.

RESULTS

A total of 18 studies involving 1251 patients with CSP, all of whom received preoperative HIFU therapy were included. The average hospital stay was 6.22 days, the intraoperative blood loss was 26.29 ml and the incidence of adverse events was 15.60%, including abdominal or lower limb pain, fever, vaginal bleeding, haematuria and vomiting. Furthermore, post-treatment follow-up showed that serum β-human chorionic gonadotropin levels were rapidly normalized (average of 25.48 days) and menstruation returned (average of 33.03 days). The treatment had a remarkable success rate of 97.60% and a subsequent pregnancy rate of 68.70%.

CONCLUSION

While the combination of HIFU and suction-curettage may induce common adverse effects such as lower abdominal or limb pain, these reactions typically do not necessitate therapeutic intervention. Additionally, the size of the gestational sac is a determinant of the procedure's success. In conclusion, HIFU combined with suction curettage demonstrates promising clinical efficacy, safety and favourable reproductive outcomes in managing CSP.

MR thermometry imaging for low intensity focused ultrasound modulation of spinal nervous tissue

OBJECTIVES

Previously in rodent and swine models, we have shown that external low intensity focused ultrasound (liFUS) can be used to modulate pain responses. To ensure no adverse heating events occur with liFUS modulation in a non-invasive manner, we perform initial work in swine to show that magnetic resonance thermometry imaging (MRTI) is capable of measuring <2.0 °C changes at the L5 DRG. Further, we show that our device can be constructed in an MR-compatible fashion to minimize artifact.

METHODS

Three MRTI techniques (referenceless, corrected proton resonance frequency shift (PRFS), and PRFS) were applied to assess accuracy of detecting thermal changes at the L5 DRG in unheated euthanized swine. A region of interest (ROI) that includes the L5 DRG was delineated, within which MRTI temperature changes were spatially averaged (ground truth 0 °C). In separate experiments with phantoms, B0 field-inhomogeneity, RF transmit (B1+) and fast gradient echo (fSPGR) magnitude images were acquired to downselect liFUS device materials that produce the least MRI artifacts.

RESULTS

Referenceless, corrected PRFS, and PRFS MRTI resulted in temperature measurements of 0.8 ± 1.1 °C, 1.1 ± 1.3 °C and 5.2 ± 5 °C, respectively. Both materials caused B0 perturbation but minimal B1+ and MRTI artifacts. The presence of imaging artifacts did not preclude thermal imaging of the region.

SIGNIFICANCE

We provide preliminary data suggesting that referenceless MRTI can adequately detect small thermal changes at the DRG that may occur with neuromodulation, which is one of the first steps in creating a table of safe parameters for liFUS therapy in humans.

Efficacy and Safety of High-intensity Focused Ultrasound Compared with Uterine Artery Embolization in Cesarean Section Pregnancy: A Meta-analysis

OBJECTIVE

To investigate the efficacy and safety of high-intensity focused ultrasound (HIFU) compared with uterine artery embolization (UAE) in cesarean section pregnancy (CSP) and to calculate the success rate of HIFU.

DATA SOURCES

We searched PubMed, Cochrane, Scopus, Web of Science, and Embase on September 30, 2022, and the related studies were independently reviewed by 2 researchers.

METHODS OF STUDY SELECTION

Medical subject headings and relevant terms from other articles were used for the database search. Patients with CSP who underwent HIFU were included in this analysis. The following results were recorded: success rate, intraoperative blood loss, time for serum beta-human chorionic gonadotropin (beta-HCG) normalization and menstruation recovery, adverse events, hospitalization time, and hospitalization expenses. We used the Newcastle-Ottawa Scale scoring system and the methodological index for nonrandomized studies system to evaluate the quality of the studies.

TABULATION, INTEGRATION, AND RESULTS

Data from 6 studies were used to compare the efficacy and safety of UAE and HIFU. We pooled the success rate of HIFU by including 10 studies. No data overlap between the 10 studies. Success rate was higher in the HIFU group (odds ratio [OR] = 1.90; 95% confidence interval [CI] 1.06-3.41; p = .03; I2 = 0). We performed the meta-analysis of single rate in R 4.2.0 software, and the success rate of HIFU group was 0.94 (95% CI 0.92-0.96; p = .04; I2 = 48%). Intraoperative blood loss (mean difference [MD]= -21.94 mL; 95% CI -67.34 to 23.47; p = .34; I2 = 99%) and time for serum beta-HCG normalization (MD = 3.13 days; 95% CI 0.02-6.25; p = .05; I2 = 70%) were not significantly different. Time to menstruation recovery (MD = 2.72 days; 95% CI 1.32-4.12; p = .0001; I2 = 0) in the UAE group was shorter than that in the HIFU group. Adverse events were not significantly different between the 2 groups (OR = 0.53; 95% CI 0.22-1.29; p = .16; I2 = 81%). Hospitalization time was not significantly different between the HIFU and UAE groups (MD = -0.41 days; 95% CI -1.14 to 0.31; p = .26; I2 = 55%). Hospitalization expenses of the HIFU group were lower than those of the UAE group (MD = -7488.49 yuan; 95% CI -8460.13 to -6516.84; p <.000; I2 = 0). Heterogeneity of the time for beta-HCG normalization, adverse events, and hospitalization time were improved after excluding one study, and HIFU showed better results in the sensitivity analysis of adverse events and hospitalization time.

CONCLUSION

According to our analysis, HIFU demonstrated satisfactory treatment success, accompanied by similar intraoperative blood loss, slower normalization of beta-HCG levels, and menstruation recovery, but potentially shorter hospitalization time, lower adverse events and lower costs than UAE. Therefore, HIFU is an effective, safe, and economical treatment for patients with CSP. These conclusions should be interpreted with caution because of the significant heterogeneity. However, large and strictly designed clinical trials are required to verify these conclusions.

Is High-intensity Focused Ultrasound Superior to Uterine Artery Embolization in Cesarean Scar Pregnancy and Subsequent Pregnancy Outcomes? A Meta-analysis of the Chinese Population

OBJECTIVE

High-intensity focused ultrasound (HIFU) followed by curettage or uterine artery embolization (UAE) followed by curettage are relatively effective methods for cesarean scar pregnancy (CSP), which can provide a high success rate and repregnancy while reducing blood loss and adverse events. Therefore, we conducted this meta-analysis to evaluate the efficacy, safety, and pregnancy outcomes of HIFU groups versus UAE groups with CSP.

DATA SOURCES

The PubMed, EMBASE, Cochrane, China National Knowledge Infrastructure, and Wanfang databases were systematically searched to find studies that compared the therapeutic effects of HIFU groups versus UAE groups.

METHODS OF STUDY SELECTION

Our primary end points were blood loss, adverse events, success rate, and repregnancy. We implemented random-effects models or fixed-effects models to evaluate the pooled data.

TABULATION, INTEGRATION, AND RESULTS

Thirty-four eligible items were included in studies. The blood loss was significantly reduced in HIFU groups compared with UAE groups (standardized mean difference = -1.45, 95% confidence interval [CI], 2.21 to -0.68; p <.001). Significantly fewer adverse events occurred in the HIFU groups than in UAE groups (odds ratio [OR] = 0.36, 95% CI, 0.23-0.57; p <.001). The success rate of HIFU groups was higher than that of UAE groups (OR = 1.56, 95% CI, 1.05-2.32; p = .03). There were more pregnancies in HIFU groups than in UAE groups (OR = 1.64, 95% CI, 1.28-2.11; p <.001).

CONCLUSION

In the CSP, the effect of HIFU groups was better than that of UAE groups: less blood loss, high success rate, fewer adverse events, and favorable fertility protection. Thus, it is a promising therapeutic method for patients.

Clinical efficacy and re-pregnancy outcomes of patients with previous cesarean scar pregnancy treated with either high-intensity focused ultrasound or uterine artery embolization before ultrasound-guided dilatation and curettage: a retrospective cohort study

BACKGROUND

Cesarean scar pregnancy (CSP) treated with either high-intensity focused ultrasound ablation (HIFU-a) or uterine artery embolization (UAE) combined with ultrasound-guided dilation and curettage (USg-D&C) was effective. However, there is insufficient comparative research evidence on clinical efficacy and subsequent pregnancy outcomes after previous CSP treatment. This study aims to investigate the efficacy, safety, and subsequent pregnancy outcomes of HIFU-a compared to UAE before USg-D&C for the treatment of CSP.

METHODS

Between January 2016 and July 2020, a total of 272 patients received the pretreatment with HIFU-a or UAE(HIFU-a group: n = 118; UAE group: n = 154). The clinical characteristics, treatment success rate, postoperative pregnancy rate and outcome of the two groups were compared and analyzed.

RESULTS

The demographic characteristics of the two groups were similar. After pretreatment, the adverse events rate of HIFU-a group was lower than that of UAE group (10.40% (16/154) vs. 40.70% (48/118), P = 0.00). All patients received the USg-D&C. The HIFU-a group was of less intraoperative blood loss (10.00 (5.00-20.00) vs. 12.50 (5.00-30.00) ml, P = 0.03). There was no statistically significant difference between the two groups in success rates. However, the HIFU-a group was of a shorter duration of postoperative vaginal bleeding (12.00 (9.00-13.00) vs. 14.00 (12.00-15.00) days, P = 0.00). There was no significant difference between the two groups in terms of subsequent pregnancy rates (P = 0.317). However, the recurrent CSP (rCSP) rate in the HIFU-a group was lower than that in the UAE group (7.70% (6/78) vs. 19.70%(13/66), P = 0.03).

CONCLUSIONS

CSP treated with either HIFU-a or UAE combined with USg-D&C was safe and effective. Although no significant difference was found in the subsequent pregnancy outcomes of the two groups, the rCSP was more common in the UAE group. So, we recommend HIFU-a combined with USg-D&C treatment modality.

Comparison of menstruation recovery after ultrasound-guided suction curettage in patients with cesarean scar pregnancy pretreated using high-intensity focused ultrasound and uterine artery embolization

OBJECTIVES

To investigate the menstruation recovery after two therapeutic regimens, high-intensity focused ultrasound (HIFU) or uterine artery embolization (UAE) combined with ultrasound-guided suction curettage, for premenopausal women with cesarean scar pregnancy (CSP).

MATERIALS AND METHODS

Seventy patients with CSP treated with HIFU followed by ultrasound-guided suction curettage and 63 patients with CSP treated with UAE followed by ultrasound-guided suction curettage in our hospital were retrospectively reviewed. The treatment parameters and the menstrual blood loss (MBL) volume at 6 months after the two therapeutic regimens were compared between the two groups.

RESULTS

There was no significant difference in treatment results between the two groups. With regard to postoperative MBL volume, 5 out of 70 patients in the HIFU group and 22 out of 63 patients in UAE group exhibited a reduction in MBL, respectively. Multivariate logistic regression revealed that hypomenorrhea was more likely to occur in the UAE group than in the HIFU group (UAE group vs. HIFU group; OR 11.328, 95% CI 3.158-55.871; p < 0.001).

CONCLUSION

Compared to UAE, HIFU has less influence on postoperative MBL volume, which may be a fertility-sparing option for patients with CSP.

High intensity focused ultrasound combined with ultrasound-guided suction curettage treatment for cesarean scar pregnancy: a comparison of different HIFU sonication strategies

OBJECTIVE

To explore a new high-intensity focused ultrasound (HIFU) sonication strategy for cesarean scar pregnancy (CSP) and to compare the clinical effectiveness and safety of this new HIFU sonication strategy with the conventional HIFU sonication strategy followed by ultrasound-guided dilation and curettage (USg-D&C) for CSP.

MATERIALS AND METHODS

91 patients with CSP treated by HIFU and USg-D&C in People's Hospital of Deyang City between January 2017 and December 2019 were retrospectively reviewed in this study. Based on the HIFU sonication strategy, patients were divided to two groups: 44 patients were exposed to 'C-shape' sonication layer by layer around the implantation location of the pregnancy sac (control group), while the other 47 patients were exposed to 'I-shape' sonication layer by layer only on the deep part which close to the bladder of the implantation location of the pregnancy sac (experimental group). The differences in clinical efficacy between the two groups were analyzed. Baseline characteristics, technical parameters of HIFU treatment and USg-D&C data were recorded. Adverse events were also recorded.

RESULTS

No statistically significant difference was observed between the two groups in baseline characteristics including age, body mass index (BMI), menopause time, largest diameter of gestational sac, pretreatment serum β-hCG, thickness of gestational sac, embedding myometrium, previous cesarean sections and interval from last cesarean section (CS). The average treatment intensity in the experimental group was significantly lower than that in the control group (p < .05). The median sonication time, total energy used for HIFU ablation, and energy efficiency factor (EEF) in the experimental group were significantly lower than the control group (p < .05). No statistically significant difference was observed between the two groups in treatment power and treatment time (p > .05). Sciatic/buttock pain and postoperative lower abdominal pain in the control group were significantly stronger than that in the experimental group (p < .05). There were no statistically significant differences in post-HIFU vaginal bleeding and discharging, urinary tract irritation, the operation time of USg-D&C, the amount of vaginal bleeding during USg-D&C, and the time for serum β-hCG back to a normal level between the two groups (p > .05).

CONCLUSIONS

The 'I-shape' strategy of HIFU treatment for CSP was effective and safe, with shorter sonication time, less energy input and lower incidence of sonication-related pain occurred in postoperative lower abdominal and sciatic nerve/buttock.

High-intensity focused ultrasound compared with uterine artery chemoembolization with methotrexate for the management of cesarean scar pregnancy

OBJECTIVE

To compare the effectiveness and safety of high-intensity focused ultrasound (HIFU) versus uterine artery chemoembolization with methotrexate for the management of cesarean scar pregnancy (CSP).

METHODS

A total of 170 women with CSP were enrolled in the retrospective cohort study from April 2016 to September 2020. One hundred women received HIFU followed by suction curettage, and 70 women were treated with uterine artery chemoembolization followed by suction curettage.

RESULTS

The median blood loss during suction curettage was 20 ml (range 2-800 ml) in the HIFU group versus 20 ml (range 5-200 ml) in the chemoembolization group (P = 0.837). The mean time for β-human chorionic gonadotropin normalization was 28.52 ± 10.82 days versus 26.69 ± 8.97 days (P = 0.246), respectively. The mean time of menstruation recovery was 34.36 ± 10.63 days versus 31.93 ± 8.53 days (P = 0.114), respectively. The incidence of adverse effects in the HIFU group was lower than that in the chemoembolization group (P = 0.028). The median hospitalization time in the HIFU group was longer than that in the chemoembolization group (P = 0.000).

CONCLUSION

HIFU was as effective and safe as uterine artery chemoembolization in the management of CSP, and the incidence of adverse effects was lower.

Pilot study on the effects of low intensity focused ultrasound in a swine model of neuropathic pain

OBJECTIVE

The authors' laboratory has previously demonstrated beneficial effects of noninvasive low intensity focused ultrasound (liFUS), targeted at the dorsal root ganglion (DRG), for reducing allodynia in rodent neuropathic pain models. However, in rats the DRG is 5 mm below the skin when approached laterally, while in humans the DRG is typically 5-8 cm deep. Here, using a modified liFUS probe, the authors demonstrated the feasibility of using external liFUS for modulation of antinociceptive responses in neuropathic swine.

METHODS

Two cohorts of swine underwent a common peroneal nerve injury (CPNI) to induce neuropathic pain. In the first cohort, pigs (14 kg) were iteratively tested to determine treatment parameters. liFUS penetration to the L5 DRG was verified by using a thermocouple to monitor tissue temperature changes and by measuring nerve conduction velocity (NCV) at the corresponding common peroneal nerve (CPN). Pain behaviors were monitored before and after treatment. DRG was evaluated for tissue damage postmortem. Based on data from the first cohort, a treatment algorithm was developed, parameter predictions were verified, and neuropathic pain was significantly modified in a second cohort of larger swine (20 kg).

RESULTS

The authors performed a dose-response curve analysis in 14-kg CPNI swine. Specifically, after confirming that the liFUS probe could reach 5 cm in ex vivo tissue experiments, the authors tested liFUS in 14-kg CPNI swine. The mean ± SEM DRG depth was 3.79 ± 0.09 cm in this initial cohort. The parameters were determined and then extrapolated to larger animals (20 kg), and predictions were verified. Tissue temperature elevations at the treatment site did not exceed 2°C, and the expected increases in the CPN NCV were observed. liFUS treatment eliminated pain guarding in all animals for the duration of follow-up (up to 1 month) and improved allodynia for 5 days postprocedure. No evidence of histological damage was seen using Fluoro-Jade and H&E staining.

CONCLUSIONS

The results demonstrate that a 5-cm depth can be reached with external liFUS and alters pain behavior and allodynia in a large-animal model of neuropathic pain.

Clinical efficacy analysis of different therapeutic methods in patients with cesarean scar pregnancy

OBJECTIVE

The purpose of this study was to analyze the clinical efficacy of five therapeutic strategies in patients with CSP.

MATERIALS AND METHODS

A total of 135 CSP patients were included and divided into five groups based on the treatment they received, including transvaginal resection (Group A), laparoscopic resection (Group B), uterine arterial embolization (UAE) combined with hysteroscopic curettage (Group C), UAE combined with uterine curettage (Group D), and hysteroscopic curettage (Group E). To investigate the clinical efficacy of these strategies, intraoperative bleeding, serum β-hCG levels and recovery time, menstruation recovery time, hormone levels at 1 month after treatment.

RESULTS

Patients in group A had the lowest postoperative serum β-hCG levels, and the shortest recovery times of both serum β-hCG and menstruation, followed by patients in group B. Group C and D had small amount of blood loss. The hospital stays and costs were low in group E. In addition, the sex hormone levels showed no significant difference among the five groups.

CONCLUSION

Our results indicated that resection surgery and UAE have good curative effects, but high hospital costs in CSP treatment. The selection of an optimal treatment regimen for CSP should be carried out based on specific conditions of the patients.

Contrast-Enhanced Ultrasound Evaluation of Mifepristone for Treatment of Low-Risk Cesarean Scar Pregnancy

Purpose

The effect of mifepristone for treatment of low-risk cesarean scar pregnancy (CSP) was monitored by contrast-enhanced ultrasound (CEUS).

Methods

Data were collected from 23 CSP patients with a 10-point risk score <5 (low-risk CSP) and from 23 intrauterine pregnancy (IUP) patients with a scar from a previous cesarean delivery. All patients were prescribed 75 mg mifepristone daily for 2 days and underwent transvaginal CEUS before and after administration of mifepristone. On the third day, uterine curettage was performed after transvaginal CEUS. Arrival time (AT), peak intensity (PI), and area under the curve (AUC) around the gestational sac were monitored by CEUS before and after application of mifepristone, and the rate of effective treatment was compared between the two patient groups.

Results

No patients experienced side effects from either the CEUS procedure or the mifepristone treatment. Changes in AT, PI, and AUC index from before vs. after mifepristone treatment did not differ significantly between the two groups (all p values >0.05). There was also no significant difference in the rate of effective treatment between the two groups (95.65% in the CSP group vs. 100% in the IUP group; p > 0.05).

Conclusions

Based on monitoring by CEUS, the effect of mifepristone in low-risk CSP was comparable to that in IUP.

Clinical Assessment of Ultrasound-Guided Local Lauromacrogol Injection Combined With Curettage and Hysteroscopy for Cesarean Scar Pregnancy

Background: To evaluate the efficacy, safeness and cost of ultrasound-guided local lauromacrogol injection (USG-LLI) combined with curettage and hysteroscopy for cesarean scar pregnancy (CSP).

Methods: This was a retrospective study included 151 CSP patients diagnosed with CSP from June 2017 to December 2019, and treated by USG-LLI (n = 86) or uterine artery embolization (UAE) (n = 65) combined with curettage and hysteroscopy. Clinical data and outcome were analyzed.

Results: There were no significant differences in basic clinical characteristics in the two groups. Two groups showed the similar success rates. USG-LLI group, compared with UAE group had significantly lower complication rates (9.30 vs. 44.62%), lower total costs (both medical and non-medication cost) (p < 0.05).

Conclusions: USG-LLI combined with curettage and hysteroscopy is a feasible method to treat CSP with minimal invasion and high efficacy. Moreover, compared with curettage after UAE, USG-LLI exhibited lower complication rate and required fewer expenses.

Comparing the Efficacy and Safety of High-Intensity Focused Ultrasound and Uterine Artery Embolization in Caesarean Scar Pregnancy: A Meta-analysis

INTRODUCTION

High-intensity focused ultrasound (HIFU) followed by curettage and uterine artery embolization (UAE) followed by curettage are two methods of treatment for caesarean scar pregnancy (CSP). There is currently no consistent evidence concerning any difference in efficacy and safety between UAE and HIFU. Therefore, a meta-analysis was performed to compare the efficacy and safety of HIFU and UAE in the treatment of CSP.

METHODS

Studies published in PubMed, Cochrane, Embase, Web of Science, Chinese BioMedical Literature Service System, and Chinese National Knowledge Infrastructure databases were searched and the main outcomes in the studies were extracted.

RESULTS

Of 8 studies and 715 patients included in this study, 388 and 327 patients were in the HIFU group and UAE groups, respectively. Compared with the UAE group, patients in the HIFU group had less blood loss [weighted mean difference (WMD) = - 22.58 ml; 95% confidence interval (CI) - 44.45 to - 0.70; p < 0.05), lower incidence of adverse events [odds ratio (OR) = 0.17; 95% CI 0.06-0.46; p < 0.05); shorter duration of hospital stay (WMD = - 0.96 days; 95% CI - 1.88 to - 0.03; p < 0.05); and a longer β-human chorionic gonadotropin normalisation time (WMD = 9.59 days; 95% CI 1.66-17.52; p < 0.05).

CONCLUSION

Patients in the HIFU group appeared to have better outcomes than those in the UAE group; thus, HIFU may be a priority option for the early management of CSP. However, this needs to be confirmed by multi-centre, large-scale randomised controlled trials.

HIFU Drive System Miniaturization Using Harmonic Reduced Pulsewidth Modulation

Switched excitation has the potential to improve on the cost, efficiency, and size of the linear amplifier circuitry currently used in high-intensity focused ultrasound (HIFU) systems. Existing switching schemes are impaired by high harmonic distortion or lack array apodisation capability, so require adjustable supplies and/or large power filters to be useful. A multilevel pulsewidth modulation (PWM) topology could address both of these issues but the switching-speed limitations of transistors mean that there are a limited number of pulses available in each waveform cycle. In this study, harmonic reduction PWM (HRPWM) is proposed as an algorithmic solution to the design of switched waveforms. Its appropriateness for HIFU was assessed by design of a high power five-level unfiltered amplifier and subsequent thermal-only lesioning of ex vivo chicken breast. Three switched waveforms of different electrical powers (16, 26, 35 W) were generated using the HRPWM algorithm. Lesion sizes were measured and compared with those made at the same electrical power using a linear amplifier and bi-level excitation. HRPWM produced symmetric, thermal-only lesions that were the same size as their linear amplifier equivalents ( ). At 16 W, bi-level excitation produced smaller lesions but at higher power levels large transients in the acoustic waveform nucleated undesired cavitation. These results demonstrate that HRPWM can minimize HIFU drive circuity size without the need for filters to remove harmonics or adjustable power supplies to achieve array apodisation.

Different Surgical Approaches to 313 Cesarean Scar Pregnancies

STUDY OBJECTIVE

To evaluate the efficacy of different surgical treatments for cesarean scar pregnancy (CSP).

DESIGN

Retrospective study (Canadian Task Force classification II-3).

SETTING

Affiliated university hospitals.

PATIENTS

Women (n = 313) with CSP.

INTERVENTIONS

Dilation and curettage under ultrasound guidance (DCUS, n = 124), dilation and curettage with hysteroscopic guidance (DCH, n = 103), vaginal excision (n = 55), laparotomy (n = 12), and laparoscopy (n = 19).

MEASUREMENTS AND MAIN RESULTS

Undetectable serum human chorionic gonadotropin (hCG) levels and thickness of the uterine scar were measured before and after surgery. Success rates of the 5 surgical treatments of CSP (DCUS, DCH, vaginal excision, laparotomy, and laparoscopy) ranged between 89% and 100%. Postoperative treatment was not needed in the vaginal and laparotomy groups, and vaginal treatment was associated with shorter operative time than laparotomy and laparoscopy and shorter time to undetectable hCG levels than DCUS and DCH. Serum hCG levels on day 3 after surgery were significantly lower than baseline levels in all groups of patients, but there was no significant difference between levels on days 3 and 5 postoperatively. Median scar thickness after surgery in the vaginal surgery, laparotomy, and laparoscopy groups was thicker than that in the DCUS and DCH groups.

CONCLUSION

In certain circumstances, CSP can be treated simply by DCH or DCUS. However, time to undetectable hCG levels is prolonged compared with more invasive techniques.