Diagnostic value of saline infusion sonohysterography for detecting endometrial focal lesion

Introduction Different diagnostic tools are available to evaluate endometrial focal lesion such as hysteroscopy, sonohystrography and transvaginal ultrasound. The present study aimed to determine the diagnostic value of saline infusion sonohystrography (SIS) in diagnosis of intrauterine lesions in women with Abnormal Uterine Bleeding (AUB). Methods This cross-sectional study recruited 100 married women with chief complain of AUB referred to gynecologic clinics at the Amir Al-Momenin hospital, Semnan, Iran from March 2014 to February 2016. All participants were in the reproductive age and post-menopausal period that showed abnormal endometrial thickness or endometrial focal lesions through transvaginal ultrasound. Participants underwent SIS, hysteroscopy plus focal lesion resection and endometrial biopsy in order. The gold standard was the histopathology of endometrial specimen reported by pathologist. Results Mean±SD age of women was 41.2±11.3 years. To diagnose the overall focal lesions, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the SIS were 79.6, 89.1, 89.6, and 78.8% respectively. These figures were 75.0, 87.5, 82.5 and 81.7%, respectively to diagnose polyps. The SIS sensitivity, specificity, PPV and NPV values to diagnose the myomas were 60.0, 97.8, 75.0, and 95.7% respectively. Conclusion Findings show that, SIS probably is a proper method for detecting endometrial focal lesion including polyps and myomas. Future studies may help to define further advantages of this procedure.


Introduction
Abnormal uterine bleeding (AUB) is one of the most common disorders in women at the childbearing age. The AUB can cause complications in personal and social life [1]. The AUB term refers to any change and irregularity of menstrual cycle and covers all changes in the duration, number, and amount of bleeding [2,3]. Although it has been estimated that more than 30% of referrals to the women health centers are related to the AUB; it is worth to notice that some patients may not be referred [1]. This fact might explain why the prevalence of the AUB in different studies had a range from 10 to 52% [4][5][6]. The AUB has numerous disadvantages on patients' health-related quality of life (HRQL) such as loosing concentration on the jobs [3], treatment costs [7] and iron storage deficiency [8]. The HRQL, as defined by the World Health Organization (complete personal, social, psychological and spiritual health), is frequently used regarding bleeding disorders, particularly AUB [9][10][11][12]. In the UK, the AUB has been considered as a cause of physical and psychosocial health problems and total quality of life as a result of the medical and paramedical effects [13] that highlights the need to assess the AUB early and with tools that are reliable and valid. There are different diagnostic tools to evaluate the endometrial focal lesions. The main and the most common tools are transvaginal sonography, sonohystrography and hysteroscopy. This variety of tools makes the first choice difficult and controversial.
Transvaginal Sonography (TVS) is the first measure to diagnose abnormal endometrium proliferation in the AUB condition in the preand post-menopausal ages [14,15], while, Saline Infusion Sonohystrography (SIS) seems to be superior to TVS, for uterine pathologies [16]. The SIS is usually carried out by entering the sterile saline into uterine cavity [14] and should be done on specific days (days 3 to 7 of the menstrual cycle and the best is day 6 th that is close to the end of bleeding period), when the Endometrial Cavity is thin [17,18]. Diagnostic hysteroscopy with endometrial biopsy is gold standard [19,20], allows inside vision of the uterus to diagnose and treat the causes of abnormal bleeding [20]. The study by Kelelci et al.
in Turkey, reported the sensitivity and specificity of the SIS (81.3 and 100%, respectively), to be higher than TVS (56.3 and 72%, respectively) and it is almost the same as hysteroscopy (87 and 100%, respectively) [21]. The high sensitivity (91.9%) and specificity

Results
Mean±Standard Deviation (SD) age of women was 41.2±11.3 years. Table 1 shows other characteristics information of women. The mean±SD endometrial thickness in SIS was 9.2±3.2 mm. Polyp was the most common focal lesion found by the SIS (40.0%) and the hysteroscopy (47.0%). However, Myoma was detected only in eight percent of the participants using the SIS and in nine percent of the participants through the hysteroscopy. Table 2 shows the agreement between the findings of the three different methods and the pathological findings. Table 3  for submucous myomas.

Discussion
The present study confirmed that the SIS has good sensitivity and very good specificity, PPV and NPV to detect the endometrial focal lesion. However, its sensitivity, specificity, PPV and NPV were less than those of the hysteroscopy and better than the TVS. • SIS is one of the diagnostic tools of endometrial focal lesion; • In some study saline infusion sonohystrography has high efficiency in diagnosis of endometrial focal lesions that is very near to hysteroscopy.

What this study adds
• Saline infusion sonohystrography probably is a proper method for detecting endometrial focal lesions including polyps and myomas; • Saline infusion sonohystrography is a suitable method for diagnosis of endometrial focal lesions prior hysteroscopy, but it could not be as an alternative of hysteroscopy (sensitivity and specifity respectively 79.6%, 89.1% for overall endometrial lesions).

Competing interests
The authors declare no competing interests.

Authors' contributions
Sanam Moradan conception and design, interpretation, manuscript writing. Sati Nik Darzi, conception and design, data collection. Raheb Ghorbani conception and design, data analysis and interpretation, manuscript writing.

Acknowledgments
The authors thank the Semnan University of Medical Sciences, Semnan, Iran (Islamic Republic of) because of financial support. We thank Dr Masoomeh Salmani (Assistant Professor in Speech Therapy) for comments that greatly improved the manuscript. Table 1: demographic variables in the study group (n=100)