The diagnosis of endometriosis is often difficult and this is secondary to a number of factors: Lack of awareness, incomplete understanding of the disease, heterogeneity of endometriosis, and co-existing diseases make the diagnosis complex. The mean delay from first symptom to diagnosis of endometriosis is around 8 years¹. Many symptoms may first appear during adolescence and are often ignored as being ‘’normal’’. A detailed clinical history and examination are of paramount importance; however, they are rarely enough on their own. Before going further, we have to, at this point, remember the 3 types of the disease².

1. Superficial Peritoneal Lesions: Classically, this type of disease is diagnosed through laparoscopic surgery³. This allows the gynaecological surgeon to directly visualise and, if possible, remove them at the same time. Since these lesions are only superficial, it remains technically challenging to diagnose them with non-invasive methods⁴. Although non-invasive methods have been described in the diagnosis of this type of disease⁵, their use is not yet widespread. Inhibition of ovulation through the use of hormones is useful in reducing the number of diagnostic laparoscopies.
2. Endometrioma: This type of the disease has typical appearance, both in the transvaginal ultrasound as well as in Magnetic Resonance Imaging (MRI). Since ultrasound costs less than MRI, it is the first-line diagnostic tool in this type of disease.
3. Deep Infiltrating Endometriosis: This type of disease can also be diagnosed by non-invasive methods.There are different views as to whether MRI is superior to ultrasound^6-10. We also need to take into account the location of the disease and the expertise of the clinician performing the test¹¹. It has also been shown that the detailed pelvic ultrasound scan takes significantly more time compared to the routine pelvic scan¹². Both the ultrasound as well as the MRI are also useful in the diagnosis of adenomyosis (presence of endometrium within the myometrium) that often co-exists with endometriosis.

It is worth noting that there are protocols for the detailed description¹³, as well as staging of the disease¹⁴, with the use of ultrasound. Their detailed description is not the aim of this article.

The use of biomarkers in the blood and urine of patients with an aim to diagnose the disease has been studied extensively, however, for the time being, it cannot replace the aforementioned diagnosis techniques^15-17.

In summary, the problem starts with the delay in the diagnosis of the disease (70% of adolescent girls with pelvic pain will later be diagnosed with endometriosis). Prompt and correct diagnosis can lead to prompt and correct management of endometriosis. 

References:

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