This was a prospective study including 200 patients with chronic pelvic pain during the period from March 2018 to February 2019. The patients were referred to our department from the gynecology and urology departments after their clinical assessment.
Inclusion criteria
Married female patients with history of chronic pelvic pain characterized by:
Exclusion criteria
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Patients with contraindications for contrast media injection
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History of abdomino pelvic malignancy
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History of prior hysterectomy and oophorectomy
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Patients with iliofemoral DVT
Proper clinical history including patient’s age, marital history, parental history, and past history of related significance was obtained. Verbal consent was considered including procedure description and benefits. Levels of serum creatinine were measured for all patients.
Imaging procedure
There was no specific preparation for contrast-enhanced CT, except that the patient should consume nothing but clear liquids 4 h prior to the examination.
Contrast-enhanced CT was performed to all cases using the 64 detector CT scanners (Lightspeed VCT, GE Healthcare, Waukesha, WI) and (Aquilion, Toshiba Medical Systems). The parameters of the volume CT scanning were as follows: tube voltage was 120 kV; tube current was 200–250 mAs; slice thickness was 5 mm; the pitch was of 1.375 mm/r; 0.8 s was set for the tube to rotate 1 cycle; and the scan matrix was 512 × 512 matrices.
The CT scan covered the area from the renal upper pole to the pelvic floor. Both plain CT scans and enhanced CT scans (including arterial, venous, and secretory phases) were performed for all patients. Via a power injector, 80–100 mL of Omnipaque 300 mg I/ml (iohexol 300 mg I/ mL; Nycomed, Princeton, NJ) was injected intravenous (IV) at a rate of 4 mL/s as the contrast agent. CT number monitoring scanning was used for the arterial phase, followed by the venous phase scanning after an interval of 30 s. After another interval of 7–10 min, the secretory phase scanning, which covered the area from the lower pole of the 11th thoracic vertebra to the pelvic cavity, was performed. A workstation was used for the post-processing of the images, particularly the multiple planar reconstruction (MPR), volume rending (VR), and curved plane reconstruction (CPR) of the venous phase images.
Imagine analysis
All scans were downloaded from DICOM server to workstation, and two radiologists experienced on abdominopelvic radiology examined the images.
Images during arterial phase were used to rule out possible reflux into ovarian veins, and images from venous phase were used for the assessment of pelvic and ovarian veins as well as identifying drainage locations of ovarian veins to renal vein or IVC. Also, the venous phase was used for assessment of abdominal and pelvic organs. The plain and secretory CT phases were used for assessment of the urinary system to exclude urological causes of the pain.
First, the CT images were assessed for presence of organic masses, enlarged lymph nodes, or any lesions which may be the cause of the chronic pelvic pain or causing vascular obstruction and secondary PCS.
The assessment of ovarian veins included their diameters and drainage location to renal vein or IVC. Maximum diameters of both ovarian veins were measured in the axial plane. The widest diameters of ovarian veins from two-fold magnified images on monitor using measuring tool were registered. After observing axial sections by scrolling images for tracking the course of ovarian veins, the drainage location of ovarian veins also was noted.
The diagnosis of pelvic congestion syndrome was based on presence of dilated ovarian veins (more than 5.5 mm) and para uterine venous plexus congestion (dilated veins more than 0.5 cm, tortuous, and difficult to see separately). Filling of the veins across the midline, vulval, and thigh varicosities was also recorded.
Statistical analysis
Data entry, processing, and statistical analysis was carried out using MedCalc version 15.8 (MedCalc, Ostend, Belgium). Tests of significance (Mann-Whitney’s, Chi square, logistic and multiple regression analysis, Spearman’s correlation, and ROC Curve analysis) were used. Data were presented and suitable analysis was done according to the type of data (parametric and non-parametric) obtained for each variable. P values less than 0.05 (5%) was considered to be statistically significant.