Key messages
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The imaging tests sono-hysterosalpingography (sono-HSG), hysterosalpingography (HSG), and transvaginal hydrolaparoscopy (THL) can reliably show whether the fallopian tubes are blocked.
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HSG seems to suggest blockage of the tubes when there is none more often than sono-HSG and THL.
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We need more research comparing one test against another, and on fluid-filled tubes and magnetic resonance hysterosalpingography (MR-HSG).
Why is it important to diagnose blocked fallopian tubes?
The fallopian tubes connect the ovaries to the womb (uterus). Blocked tubes can prevent pregnancy, as the egg and sperm cannot meet. Diagnosing blocked tubes (tubal occlusion) and fluid-filled tubes (hydrosalpinx) is essential for choosing the right treatment. Traditionally, keyhole surgery (laparoscopy with dye) is used, but this method is invasive and expensive. Alternative tests have been developed using imaging methods, which are less expensive and less invasive, and can be performed during an outpatient clinic visit.
What are the imaging tests?
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Sono-hysterosalpingography (sono-HSG): salt water or foam is placed in the womb, and an internal ultrasound is used to see if the fluid passes through the fallopian tubes.
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Hysterosalpingography (HSG): a contrast fluid is placed in the womb, and X-ray pictures show whether it flows through the tubes.
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Transvaginal hydrolaparoscopy (THL): a tiny camera is placed through the vaginal wall. At the same time, salt water is placed in the womb to see if it comes through the tubes.
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Magnetic resonance hysterosalpingography (MR-HSG): similar to HSG, but a magnetic resonance imaging (MRI) scan is used to make detailed pictures of the tubes.
What did we want to find out?
We wanted to find out how well these tests can show blocked fallopian tubes and fluid-filled tubes, compared with the traditional keyhole surgery test.
What did we do?
We looked for studies that investigated these imaging tests compared to traditional keyhole surgery. We brought together the results from all the studies and checked how well each test could correctly show when the tubes are blocked and when they are fluid-filled.
What did we find?
The review included 21 studies with a total of 1939 women:
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8 studies on sono-HSG;
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8 studies on HSG;
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3 studies for TLH;
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no studies for MR-HSG;
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2 studies for sono-HSG and HSG
Only two studies on sono-HSG and two studies on HSG reported on fluid-filled tubes.
Three studies were not in English; we translated them online. Nine studies did not clearly explain whether the participants were women with a low or high risk of having blocked tubes. Seven studies did not mention whether the tests were done by a trained person.
Blocked tubes
Sono-HSG, HSG and THL are reliable tests for blocked fallopian tubes. HSG may be more likely than sono-HSG and THL to suggest that tubes are blocked when they are not.
If 1000 women were tested for blocked fallopian tubes by the different imaging tests, and 182 of them actually had blockages in both tubes (this number was based on how often the condition was actually found in the studies we included), then:
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for sono-HSG: 186 women would be told they have blocked tubes based on sono-HSG results. Of these, 8 women would actually have open tubes; 814 women would be told their tubes are open, and of these, 4 women would actually have blocked tubes.
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for HSG: 189 women would be told they have blocked tubes based on HSG results. Of these, 49 women would actually have open tubes; 811 women would be told their tubes are open, and of these, 57 women would actually have blocked tubes.
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for THL: 181 women would be told they have blocked tubes based on THL results. Of these, 8 women would actually have open tubes; 819 women would be told their tubes are open, and of these, 9 women would actually have blocked tubes.
Fluid-filled tubes
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One sono-HSG study reported results by tube and the other reported results by woman, so we could not combine their results.
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Two HSG studies reported results by tube. They showed that all women diagnosed with fluid-filled tubes had this condition, and four out of 100 women diagnosed with fluid-filled tubes did not have this condition.
What are the limitations of the evidence?
The included studies looked at blockages in a single tube, on one side, or on both sides. Only a few studies reported each of these things for each test, so it was difficult to draw conclusions. Also, only a few studies compared one imaging test against another, so we could not say for sure which test is better.
How up to date is this evidence?
The evidence is up to date to November 2023.
Leer el resumen científico
Around 18% to 33% of couples with infertility present with tubal occlusion (blocked or damaged fallopian tubes) or hydrosalpinx (fluid-filled tubes). Diagnostic laparoscopy (keyhole surgery) with chromopertubation (methylene blue dye tubal patency testing) is considered the reference standard for ruling out tubal occlusion and hydrosalpinx. However, due to its invasiveness and high costs, alternative, less invasive tests have been carried out using imaging techniques. They include sono-hysterosalpingography (sono-HSG), hysterosalpingography (HSG), outpatient transvaginal hydrolaparoscopy (THL), and magnetic resonance hysterosalpingography (MR-HSG). The choice of test varies in different settings; the choice of contrast, operator skill and test technology are factors that can influence diagnostic quality. Furthermore, the performance of the visual tubal patency tests can vary in different populations, depending on whether the test is carried out in an unselected group or in one classified as high or low risk for having tubal pathology.
Objetivos
To determine and compare the diagnostic accuracy of visual tubal patency tests (sono-HSG, HSG, THL, and MR-HSG) for the diagnosis of tubal occlusion.
Secondary objectives are to determine and compare the diagnostic accuracy of visual tubal patency tests (sono-HSG, HSG, THL, and MR-HSG) for the diagnosis of hydrosalpinx and to evaluate heterogeneity concerning population characteristics (population risk stratification) and index test characteristics (contrast media, technology, operator skills).
Métodos de búsqueda
We searched CENTRAL, MEDLINE, Embase and CINAHL, and two trials registers. We also contacted experts in the field for any additional studies (last date of search: 6 November 2023).
Criterios de selección
We included studies on the diagnostic accuracy of a single index test and studies on the comparative diagnostic accuracy of two or more index tests. Index tests included were: sono-HSG, HSG, THL, and MR-HSG. Laparoscopy with methylene blue dye tubal patency testing was the reference standard. We included participants who had been trying to conceive for at least one year. All participants in the included studies should have undergone this reference standard. Target conditions were bilateral tubal occlusion, at least one-sided tubal occlusion, tubal occlusion by tube, and hydrosalpinx.
Obtención y análisis de los datos
Two review authors independently extracted data. We performed random-effects meta-analysis in a bivariate model. For each index test, we presented pairs of sensitivity and specificity with their 95% confidence intervals (CIs) for each study, as well as the pooled sensitivity and specificity in a forest plot. We used the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool for risk of bias assessments.
Resultados principales
We identified 11,787 records and included 21 studies (1939 participants). Two studies directly compared both sono-HSG and HSG to the reference test, while the other 19 reported on the diagnostic accuracy of one of the index tests (10 on sono-HSG, 10 on HSG, and 3 on THL). We did not include any studies of MR-HSG.
Sono-HSG: for bilateral tubal occlusion, the pooled sensitivity was 0.98 (95% CI 0.19 to 1.00; 3 studies, 259 women; moderate-certainty evidence) and specificity was 0.99 (95% CI 0.93 to 1.00; 4 studies, 259 women; high-certainty evidence). Subgroup analyses showed that colour Doppler was associated with higher specificity than standard ultrasound, but with similar sensitivity. We did not find differences in diagnostic accuracy in the use of 3-dimensional/2-dimensional or 2-dimensional ultrasound, or the use of foam or saline as contrast media. We were unable to perform meta-analysis on the diagnosis of hydrosalpinx.
HSG: for bilateral tubal occlusion, the pooled sensitivity was 0.77 (95% CI 0.58 to 0.89; 7 studies, 670 women; very low-certainty evidence) and the pooled specificity was 0.94 (95% CI 0.87to 0.97; 7 studies, 670 women; moderate-certainty evidence). For hydrosalpinx by tube, the pooled sensitivity was 1.00 and specificity was 0.96 (95% CI 0.96 to 0.98; 2 studies, 360 tubes).
THL: for bilateral tubal occlusion, the pooled sensitivity and specificity were 0.95 (95% CI 0.30 to 1.00; 3 studies, 172 women; low-certainty evidence) and 0.99 (95% CI 0.84 to 1.00; 3 studies, 172 women; moderate-certainty evidence), respectively. We were unable to perform meta-analysis on the diagnosis of hydrosalpinx.
There was insufficient information on operator skills and patient risk stratification for all index tests to carry out further analyses.
Conclusiones de los autores
The evidence showed that sono-HSG, HSG and THL are all reliable tests for the diagnosis of double-sided tubal occlusion. Evidence for comparative diagnostic accuracy studies is very limited. We did not include any studies on the diagnostic accuracy of MR-HSG. The certainty of evidence ranged from very low to high. This was mainly due to unclear or high risk of bias, heterogeneity and imprecision. Limited reporting on population risk and operator experience may reduce the generalisability of the findings to routine clinical practice.
Financiación
This Cochrane review had no dedicated funding.
Registro
Protocol (2022) available via: https://doi.org/10.1002/14651858.CD014968
