A hydrosalpinx refers to a fluid collection in a distended fallopian tube with distal occlusion. The fluid collection results in a dilated and/or tubular like appearance of the fallopian tube. It is a common sequela of pelvic inflammatory disease and a major cause of infertility.
Symptoms of hydrosalpinx vary based on the cause and severity of the disease. It frequently occurs following pelvic inflammatory disease (PID). Patients may present with chronic pelvic pain, lower abdominal pain, low-grade fever, vaginal discharge, and/or non-menstrual uterine bleeding. Other patients will be completely asymptomatic except for infertility . Hydrosalpinx has also been associated with tubal and ovarian malignancy. In such cases a patient may describe a feeling of "fullness" in the pelvic region or an adnexal mass . Hydrosalpinx may be unilateral, however, the fallopian tube on the other side is also abnormal in most of the cases.
Workup for hydrosalpinx begins with the patient's medical history, physical exam, and ultrasound imaging. More invasive procedures used to diagnose hydrosalpinx include hysterosalpingography (HSP) and surgical laparoscopy. A history of pelvic inflammatory disease, sexually transmitted disease, endometriosis, infertility, previous lower abdominal or pelvic surgeries, and/or ruptured appendix should be elicited. Hydrosalpinx has been associated with tubal and ovarian malignancy, and therefore questions pertaining to patient or family history of such malignancy and/or recent unexplained weight loss and fatigue may be useful as well. Physical exam includes palpation for any adnexal or pelvic mass. A serum or urine pregnancy test should be administered to any woman of child bearing age to rule out tubal pregnancy.
Transvaginal ultrasonography has a high sensitivity and specificity for diagnosis of hydrosalpinx   . Appearance of hydrosalpinx on gray scale ultrasonography consists of an elongated, dilated fallopian tube, with incomplete septations or indentations (commonly referred to as either "waist sign" or "cogwheel"), and anechoic contents . Nodules may or may not be present in the walls; their presence should raise suspicion for ovarian malignancy . Color doppler evaluation can help differentiate hydrosalpinges from ovarian lesions; the former is characterized by flow from the borders and typically high resistance than ovarian flow  .
Magnetic resonance imaging (MRI) may be used to help identify the nature of the contents of distended fallopian tube  . For example, fluid demonstrating a high signal intensity on T1-weighted images is indicative of endometriosis or tubal pregnancy; heterogenous signal intensity in the wall of the tube suggests pylosalpinx resulting from tubo-ovarian abscess; and an enhancing solid mass inside the distended tube is suggestive of tubal carcinoma .
Hydrosalpinx is often diagnosed with a HSP. HSP findings demonstrate a dilated, distal fallopian tube showing obstructed fimbria and no spillage of contrast dye into the peritoneum (indicating occlusion) .
Laparoscopy allows for confirmatory diagnosis of hydrosalpinx as well as for intervention and treatment such as opening the occluded end of the tube, removal of adhesions, and possible removal of the fallopian tubes in certain cases.