The role of ultrasonography for evaluation of uterine cervix in patient with suspected isthmus cervical incompetence

Abstract

Istmocervical incompetence (IIC) is one of the most frequent causes of miscarriage, also responsible for 16 to 20% of gestational losses in the second trimester. It is characterized by the inability of the internal orifice to retain the concept and membranes until the term of gestation, due to the pressure exerted by them in the cervical canal. The diagnosis requires the association between clinical evaluation with sonographic assessment. For the present discussion, articles were collected from PubMed, Cochrane and Scielo databases. Identification of risk patients can be done through clinical data and the transvaginal ultrasound (USTV) by measuring the length of the cervix and the internal orifice. Also, it is considered superior to the transabdominal approach because it allows the better characterization of the cervix. The uterine compression technique associated with USTV helps to detect patients with cervical insufficiency and better characterizes the internal orifice dilatation, showing even subclinical stages, when compared to the examination performed at rest. Imaging criteria considered are shortening of the cervical canal, internal orifice dilation and exteriorization of membranes (funneling). The ultrasonography is a very important tool in the diagnosis of cervical incompetence because, along with the clinical data, it can provide diagnosis in initial phases, consequently improving the prognosis and enabling an appropriate and rapid therapeutic intervention. The transvaginal measurement of the uterine cervix is a simple, reliable and well tolerated method, highly sensitive and has a high positive predictive value of possible cervical incompetence.