Hysterosalpingography Vs Hysteroscopy in the Detection of Intrauterine Pathology in Infertility

Methods: This is a prospective comparative study done among 50 new cases of primary and secondary infertility presenting to infertility clinic of Tribhuvan University Teaching Hospital from March 2006 – 2007. HSG was performed in the proliferative phase of menstrual cycle followed by HSC in the proliferative phase of the same or the following cycle. Intra uterine findings on HSG were evaluated and compared with hysteroscopic findings.

Proper technique in performing an HSG is imperative since inadequate uterine distension may result in poor visualization and overzealous instillation may easily obscure uterine pathology. 5,6C is an outpatient procedure that does not require anaesthesia and has better patient compliance and thus constitutes a defi nitive diagnostic test. 7HSC can reveal the shape of the uterine cavity and locate submucosal lesions, congenital uterine anomalies, intrauterine adhesions (IUAs) and submucous lesions. 8Moreover, HSC is useful in identifying endometrial abnormalities not detectable on HSG. 9 HSC is more accurate than HSG because of the false positive and false negative rates associated with HSG. 10,11e objective of this study was to investigate the accuracy of HSG in comparison to HSC in the detection of intrauterine pathology in infertility.

METHODS
A prospective comparative study was conducted in Radiology department and infertility clinic, Obstetrics and Gynaecology department, TUTH, Kathnandu from March 15, 2006 -March 15, 2007.Ethical approval and patient consent was taken.Following the convenience sampling, 50 new cases of primary and secondary infertility were included in the study.Women with acute genital tract infections, suspicion of cervical malignancy, cardiorespiratory disease, ongoing pregnancy and previous history of HSG were excluded.HSG was performed in the proliferative phase of the menstrual cycle followed by HSC in the proliferative phase of the same or the following cycle consecutively to the same patient.The fi ndings of both the investigations were compared later.Data collection and statistical analysis were done by using Statistical Package for Social Science (SPSS) version 11.5.

RESULT
During the study period, there were total 520 cases of infertility attended, 140 were new cases and 380 were old cases.Out of 140, 50 of them passed through the inclusion criteria and were enrolled in the study.Out of 50 infertile women, 42 were primary infertility cases and eight were secondary infertility cases.HSG revealed normal uterine cavity in 49 women (98%) while HSC confi rmed only 44 (88%) normal uterine cavities.HSG detected only one (2%) abnormal uterine cavity whereas HSC demonstrated six (12%).One case (2%) that could be detected by HSG was subseptate uterus which was confi rmed at HSC.The six abnormal cases according to HSC were endometrial polyps, subseptate uterus and submucous myoma (Table 1, 2 In the present study, 5 (10%) of the intrauterine pathology could not be detected by HSG as compared to HSC.This fi nding is similar to various other studies. 12,13Another study stated that HSG is inaccurate in diagnosing small submucous myoma and endometrial polyp. 14This was supported by another study and mentioned that HSC was very valuable in disclosing small intrauterine lesions. 15e enthusiasm for HSC has been based on the assumption that this diagnostic procedure is able to pick up small intrauterine lesions that might not otherwise be readily diagnosed by HSG.In support of this, one study reported that HSC apparently determined the diagnosis of undetected radiographic abnormalities (small endometrial polyps, IUAs and submucous myomas) in 62% of the 142 patients examined. 16veral reports have noted unsuspected intrauterine lesions in one-third or more of patients undergoing HSC and found intrauterine lesions in 29% of their 1100 diagnostic HSC, 17 whereas two other studies 18,19 reported that HSC revealed intrauterine disease (such as endometrial polyps and IUAs) which were unsuspected or previously undetected by HSG in 39% and 44% respectively.
The differences between HSG and HSC were observed mainly in the detection of endometrial polyps and submucous myoma as HSG could not detect them.This could probably be due to the fact that the size of endometrial polyps and submucous myoma were too small for HSG to show any fi lling defect.
In this study, the accuracy rate of HSG was 90% which is close to the other studies showing accuracy rate of HSG as 73.2%, 73%, 74.1% and 74.8% respectively in comparison to HSC. 7,9,20,21 This study had no case of abnormal HSG with normal fi nding in HSC.Therefore, false positive rate of HSG is close to zero.The false negative rate is higher (83.3%).However, different other studies reported false positive rate ranging from 11.7 to 18% and false negative rate ranging from 13.3 to 35.4%. 10,21 this study, HSG in the detection of intrauterine lesions had very low SV 16.7% (95% CI 0.9-63.5),100% SP (95% CI 90-100), 100% PPV (95% CI 5.5-100) and NPV 89.8% (95% CI 77-96.2) in comparison to HSC.Hence, this study demonstrated HSG is a specifi c but not sensitive predictor of uterine pathology in infertility patients as compared with HSC which was comparable with another study. 22wever, in contrast to this study, various other studies revealed high SV, low SP, low PPV and very high NPV.As in the present study, since HSG had no FPR, HSG showed 100% SP and PPV in the detection of intrauterine pathology as compared to HSC.In the contrary, unlike other studies, this study revealed a very low SV of HSG which could be due to the fact that HSC disclosed small intrauterine lesions (10%) that were otherwise not detected by HSG.
So, when intrauterine lesion is suspected in infertility patients, HSC should be the fi rst option for direct visualization of cavity and early detection of intrauterine pathology.

CONCLUSION
This study revealed hysterosalpingography is a specifi c but not sensitive predictor of uterine pathology.Besides, hysterosalpingography did not provide any additional fi nding in comparison to hysteroscopy.Hence, it can be concluded that hysterosalpingography is not advisable in the detection of uterine pathology in infertility patients.