IDEAL framework in surgical innovation applied on laparoscopic niche repair

Reproductive outcomes after laparoscopic resection of symptomatic niches in uterine cesarean scars: Long-term follow-up on the prospective LAPNICHE study

INTRODUCTION

After incomplete healing of the uterine cesarean section scar, a niche can be observed; 24% of the women develop large niches with a residual myometrial thickness <3 mm. In these cases a laparoscopic resection is possible. The effect of this new treatment on fertility outcome is not known yet. This paper describes reproductive outcomes 2 years after a laparoscopic niche resection and compares women with or without secondary infertility at baseline.

MATERIAL AND METHODS

A prospective cohort study was performed, with consecutive inclusion of women between 2011 and 2019. Women with a niche in the uterine cesarean scar, with a residual myometrial thickness of <3 mm and with a desire to become pregnant, were scheduled to undergo a laparoscopic niche resection because of one or more of the following problems (1) postmenstrual spotting; (2) midcycle intrauterine fluid accumulation diagnosed during the fertility workup or (3) difficulties with a previous embryo transfer and preferring a surgical therapy. The study is registered in the ISRCTN register (ref. no. ISRCTN02271575) on April 23, 2013.

RESULTS

There were 133 (62%) women included with a desire to become pregnant, 88 with secondary infertility. In all, 83 had an ongoing pregnancy at the 2-year follow-up. The ongoing pregnancy rate in patients with previous fertility problems was 60.2% compared with 66.7% in patients without infertility (odds ratio [OR] 0.68, 95% confidence interval [CI] 0.32-1.7). The OR for live births was 0.57 (95% CI 0.02-1.2). Overall, 8.3% of the pregnancies resulted in miscarriages by the 2-year follow-up.

CONCLUSIONS

The reproductive outcomes in women with and without previous fertility problems undergoing resection of a large niche are very promising and quite comparable in both groups. These results suggest, but do not prove, a beneficial effect of this therapy for these indications. The results support the design of future randomized controlled trials to evaluate the effect of niche resection vs expectant management to assess its additional value in women with or without fertility problems who desire pregnancy.

Effectiveness of laparoscopic niche resection versus expectant management in patients with unexplained infertility and a large uterine caesarean scar defect (uterine niche): protocol for a randomised controlled trial (the LAPRES study)

INTRODUCTION

A uterine niche is a defect at the site of the uterine caesarean scar that is associated with gynaecological symptoms and infertility. Promising results are reported in cohort studies after a laparoscopic niche resection concerning reduction of gynaecological symptoms in relation to baseline and concerning pregnancy outcomes. However, randomised controlled trials to study the effect of a laparoscopic niche resection on reproductive outcomes in infertile women are lacking. This study will answer the question if laparoscopic niche resection in comparison to expectant management improves reproductive outcomes in infertile women with a large uterine niche.

METHODS AND ANALYSIS

The LAPRES study is a randomised, non-blinded, controlled trial, including 200 infertile women with a total follow-up of 2 years. Women with the presence of a large niche in the uterine caesarean scar and unexplained infertility of at least 1 year or failed IVF will be randomly allocated to a laparoscopic niche resection within 6 weeks or to expectant management for at least 9 months. A large niche is defined as a niche with a depth of >50% of the myometrial thickness and a residual myometrium of ≤3 mm on transvaginal ultrasound. Those receiving expectant management will be allowed to receive fertility therapies, including assisted reproductive techniques, if indicated. The primary outcome is time to ongoing pregnancy, defined as a viable intrauterine pregnancy at 12 weeks' gestation. Secondary outcome measures are time to conception leading to a live birth, other pregnancy outcomes, received fertility therapies after randomisation, menstruation characteristics, patient satisfaction, quality of life, additional interventions, and surgical and ultrasound outcomes (intervention group). Questionnaires will be filled out at baseline, 6, 12 and 24 months after randomisation. Ultrasound evaluation will be performed at baseline and at 3 months after surgery.

ETHICS AND DISSEMINATION

The study protocol was approved by the medical ethics committee of the Amsterdam University Medical Centre. (Ref. No. 2017.030). Participants will sign a written informed consent before participation. The results of this study will be submitted to a peer-reviewed journal for publication. TRIAL REGISTRATION NUMBER DUTCH TRIAL REGISTER REF NO NL6350 : http://www.trialregister.nl.

Post-Caesarean section niche-related impaired fertility: hypothetical mechanisms

Caesarean section can result in an indentation of the myometrium at the site of the Caesarean scar, called a niche. Niches can cause symptoms of abnormal uterine blood loss, dysmenorrhoea, chronic pelvic pain and dyspareunia and are possibly related to subfertility. Various other explanations for the cause of subfertility after Caesarean section have been proposed in the literature, such as uterine pathology, intra-abdominal adhesions and women’s reproductive choices. Not all niches cause symptoms and the relation with subfertility and a niche in the uterine scar still needs further study since direct evidence is lacking so far. Based on the limited available evidence, and in combination with observations made during sonographic hysteroscopic evaluations and laparoscopic niche repair, we propose and discuss three hypothetical mechanisms: (i) the environment for sperm penetration and implantation may be detrimental; (ii) there could be a physical barrier to embryo transfer and implantation; and (iii) psychogenic factors may reduce the likelihood of pregnancy. Several innovative surgical treatments have been developed and are being implemented for niche-related problems. Promising results are reported, but more evidence is needed before further implementation in daily practice. The additional value of niche resections should be compared to expectant management or fertility therapies, such as ART, in randomized controlled trials. Therefore, our suggested hypotheses should, for the time being, not be used for justification of any specific procedures outside clinical trials.

Histologic Findings of Uterine Niches

OBJECTIVES

The disruption or defect of the myometrium in the uterine scar of a cesarean section (CS) has been known by various names, such as uterine niche, isthmocele, deficient uterine scar, scar pouch, or diverticulum. Symptomatology, risk factors for niche development, and available treatment modalities have been recently studied. However, the histologic features of this disease remain unknown.

METHODS

The histologic features of eight uterine niches are thoroughly described and a summary of the most important aspects of the uterine niche literature is provided. Five cases of CS scars without niche formation are comparatively examined.

RESULTS

Most uterine niches harbor endocervical mucosa, often cystically dilated and/or an atrophic or disorganized endometrial mucosa of lower uterine segment origin. Regenerative epithelial atypia and fibroblastic stromal reaction are frequent features. No granulomatous reaction, important inflammation, or hemorrhage is seen. CS scars without niche formation do not harbor endocervical mucosa or inclusion cysts, fibroblastic stroma, or regenerative atypia.

CONCLUSIONS

As more prospective studies of uterine niche development and treatment will be conducted, a detailed pathologic report with the criteria proposed herein can be designed.

Improved health-related quality of life in the first year after laparoscopic niche resection: a prospective cohort study

OBJECTIVE

To evaluate changes in health-related quality of life (HRQOL) the first year after laparoscopic niche resection.

STUDY DESIGN

Prospective cohort study in women with a large niche (residual myometrium thickness <3.0 mm) after caesarean section who underwent laparoscopic niche resection between May 2010 and January 2018. Women were included consecutively. 36-Item Short Form Survey (SF-36) was sent at baseline, three and twelve months postoperatively. All participants that filled out the questionnaire at baseline were included. Physical (PCS) and mental component summary scores (MCS) and scores for subdomains were calculated. Scores were analysed over time using Wilcoxon signed rank test.

RESULTS

146 participants responded to the SF-36 at baseline, of which 129 (88.4 %) responded at three or twelve months follow-up. After three months, median PCS and MCS improved, compared to baseline (p = 0.014 and p = 0.008, respectively). Subdomains physical functioning, bodily pain, general health, vitality, mental health and social functioning improved significantly. At twelve months follow-up, improvement in PCS and MCS did not reach statistical significance (p = 0.053 and p = 0.063, respectively). Subdomains bodily pain (77.6-89.8, p < 0.001), mental health (76-80, p = 0.004) and social functioning (75-87.5, p = 0.016) improved significantly. Women with symptom relief as main goal of the intervention showed larger improvement in PCS than women with distorted anatomy and to restore anatomy as main goal for the intervention (p = 0.001).

CONCLUSION

Laparoscopic niche resection improves HRQOL in women with a large niche in physical and mental domains three and twelve months postoperatively.

Augmenting endogenous repair of soft tissues with nanofibre scaffolds

As our ability to engineer nanoscale materials has developed we can now influence endogenous cellular processes with increasing precision. Consequently, the use of biomaterials to induce and guide the repair and regeneration of tissues is a rapidly developing area. This review focuses on soft tissue engineering, it will discuss the types of biomaterial scaffolds available before exploring physical, chemical and biological modifications to synthetic scaffolds. We will consider how these properties, in combination, can provide a precise design process, with the potential to meet the requirements of the injured and diseased soft tissue niche. Finally, we frame our discussions within clinical trial design and the regulatory framework, the consideration of which is fundamental to the successful translation of new biomaterials.

Single- versus double-layer closure of the caesarean (uterine) scar in the prevention of gynaecological symptoms in relation to niche development - the 2Close study: a multicentre randomised controlled trial

BACKGROUND

Double-layer compared to single-layer closure of the uterus after a caesarean section (CS) leads to a thicker myometrial layer at the site of the CS scar, also called residual myometrium thickness (RMT). It possibly decreases the development of a niche, which is an interruption of the myometrium at the site of the uterine scar. Thin RMT and a niche are associated with gynaecological symptoms, obstetric complications in a subsequent pregnancy and delivery and possibly with subfertility.

METHODS

Women undergoing a first CS regardless of the gestational age will be asked to participate in this multicentre, double blinded randomised controlled trial (RCT). They will be randomised to single-layer closure or double-layer closure of the uterine incision. Single-layer closure (control group) is performed with a continuous running, unlocked suture, with or without endometrial saving technique. Double-layer closure (intervention group) is performed with the first layer in a continuous unlocked suture including the endometrial layer and the second layer is also continuous unlocked and imbricates the first. The primary outcome is the reported number of days with postmenstrual spotting during one menstrual cycle nine months after CS. Secondary outcomes include surgical data, ultrasound evaluation at three months, menstrual pattern, dysmenorrhea, quality of life, and sexual function at nine months. Structured transvaginal ultrasound (TVUS) evaluation is performed to assess the uterine scar and if necessary saline infusion sonohysterography (SIS) or gel instillation sonohysterography (GIS) will be added to the examination. Women and ultrasound examiners will be blinded for allocation. Reproductive outcomes at three years follow-up including fertility, mode of delivery and complications in subsequent deliveries will be studied as well. Analyses will be performed by intention to treat. 2290 women have to be randomised to show a reduction of 15% in the mean number of spotting days. Additionally, a cost-effectiveness analysis will be performed from a societal perspective.

DISCUSSION

This RCT will provide insight in the outcomes of single- compared to double-layer closure technique after CS, including postmenstrual spotting and subfertility in relation to niche development measured by ultrasound.

TRIAL REGISTRATION

Dutch Trial Register ( NTR5480 ). Registered 29 October 2015.

Minimally invasive vertical versus conventional tooth extraction: An interrupted time series study

BACKGROUND

Minimally invasive vertical tooth extraction techniques have evolved in light of the limitations of conventional tooth extraction techniques and flap surgery in preserving the alveolar bone. The authors conducted a study to obtain data on the performance of a vertical extraction system. This included comparing the need for flap surgery using the vertical extraction system versus conventional tooth extraction techniques for the extraction of anterior teeth and premolars not suitable for forceps extraction.

METHODS

The authors conducted a prospective observational clinical study of the vertical extraction system versus conventional tooth extraction techniques using an interrupted time series in line with the Idea, Development, Exploration, Assessment, Long-term Follow-up collaboration framework for surgical innovation.

RESULTS

Overall, 276 of 323 teeth (85.4%) in 240 patients were successfully extracted using the vertical extraction system. Of the 47 failures in the vertical tooth extraction cohort, 18 required flap surgery, resulting in an overall incidence of flap surgery of 5.6% (95% confidence interval [CI], 3.2% to 8.7%). During the routine care period, of the 94 anterior teeth and premolars in 78 patients, 21 teeth could not be extracted using conventional techniques and required flap surgery, leading to an incidence of flap surgery of 22% (95% CI, 14% to 32%).

CONCLUSIONS

The results suggest that the vertical extraction system may be used with a high success rate for extraction of severely destroyed teeth, and its use may lead to a marked reduction in the need for flap surgery. Randomized clinical trials are needed to confirm the findings.

PRACTICAL IMPLICATIONS

The use of a vertical extraction system may lower the incidence of flap surgery.

Etiology of Cesarean Uterine Scar Defect (Niche): Detailed Critical Analysis of Hypotheses and Prevention Strategies and Peritoneal Closure Debate

There is an increasing incidence of cesarean scar (CS) defect/niche and its sequelae, probably not entirely explained by better diagnosis or rising cesarean rate. Discussion of possible etiological factors has received scant attention but would be important to formulate preventive strategies. Meaningful informative studies on long-term sequelae of cesarean section are very difficult and none are available for causation of CS defect. Hence, it is crucial to identify key areas in etiology of CS defect for focused research. This practical review proposes an "ischemia and mal-apposition hypothesis for CS niche", stating that the surgical technique of uterine incision closure is the most important determinant of CS defect formation. Other factors such as cervical location incision, adhesion formation and patient specific factors seem far less important in etiology. Rather than the headline theme of "single versus double-layer closure of uterus", the finer details of surgical technique which achieve good apposition without inducing tissue ischemia seem more important. Different techniques are discussed and it is proposed that continuous, non-locking absorbable sutures in two layers, without including much of decidua and without undue tight (constricting/devasculaizing) pulling of sutures are likely to result in good healing of uterine scar. Single-layer technique may be best reserved for thin myometrial edges especially during repeat cesareans. Adhesions between uterine isthmus and bladder/abdominal wall seem common associations but not causative for CS niche. It would be desirable to prove these surgical principles by good quality prospective randomized "quantitative" studies but the wait may be very long and this should not hinder the adoption of good surgical principles. Science is much cognitive and not just empirical. To consider a related example, the current recommendation of non-suturing of peritoneal layers during cesarean is mistakenly based on short-term irrelevant surrogate outcomes like analgesic requirements and time-saving, many of which have been already disproven. Evidence is presented recommending simple quick techniques of peritoneal closure to prevent adhesions. More analytical debate in surgical techniques is needed to inspire engaged, critical and insightful practitioners rather than unquestioning dependence on weak evidence/guidance.

Technical aspects of the laparoscopic niche resection, a step-by-step tutorial

The technique of a laparoscopic niche resection is described in ten steps and alternative steps for future studies are discussed.

The effect of laparoscopic resection of large niches in the uterine caesarean scar on symptoms, ultrasound findings and quality of life: a prospective cohort study

Objective

To evaluate the effectiveness of a laparoscopic niche resection on niche‐related symptoms and/or fertility‐related problems, ultrasound findings and quality of life.

Design

Prospective cohort study.

Setting

University hospital.

Population

Women with a large niche (residual myometrium <3 mm) and complaints of either postmenstrual spotting, dysmenorrhoea, intrauterine fluid accumulation and/or difficulties with embryo transfer due to distorted anatomy.

Methods

Women filled out questionnaires and a validated menstrual score chart at baseline and 6 months after the laparoscopic niche resection. At baseline and between 3 and 6 months follow up niches were evaluated by transvaginal ultrasound.

Main outcome measures

The primary outcome was reduction of the main problem 6 months after the intervention. Secondary outcomes were complications, menstrual characteristics, dysmenorrhoea, niche measurements, intrauterine fluid, surgical outcomes, satisfaction and quality of life.

Results

In all, 101 women underwent a laparoscopic niche resection. In 80 women (79.2%) the main problem was improved or resolved. Postmenstrual spotting was significantly reduced by 7 days at 6 months follow up compared with baseline. Dysmenorrhoea and discomfort related to spotting was also significantly reduced. The residual myometrium was increased significantly at follow up. The intrauterine fluid was resolved in 86.9% of the women with intrauterine fluid at baseline; 83.3% of women were (very) satisfied. The physical component of quality of life increased, the mental component did not change.

Conclusions

A laparoscopic niche resection reduced postmenstrual spotting, discomfort due to spotting, dysmenorrhoea and the presence of intrauterine fluid in the majority of women and increased the residual myometrium.

Tweetable abstract

Laparoscopic niche resection reduces niche‐related problems and enlarges the residual myometrium.

Laparoscopic niche resection reduces niche‐related problems and enlarges the residual myometrium.