Three-Dimensional Ultrasonography versus Magnetic Resonance Imaging for Fibroid Mapping: A Cross sectional Observational study

2) Introduction: Uterine fibroids are the most prevalent gynecologic tumors, affecting nearly (20-30) % of women in the reproductive age group[1] . Approximately 50% of fibroid cases are symptomatic [2] and presented by abnormal uterine bleeding, dysmenorrhea, pressure symptoms, infertility, and pregnancy loss[3]. Fibroids are myometrium-derived monoclonal smooth muscle cancers and their growth is reliant on estrogen and progesterone levels, thus fibroids usually expand during pregnancy or during the use of combined oral contraceptives, and shrink after menopause[4]. Two dimensional ultrasound is the initial test of choice to assess the presence of fibroids in symptomatic patients as it is simple, easy, available and informative [5]. Furthermore, ultrasonography may be sufficient for individuals having conservative therapy. However, Magnetic Resonance Imaging (MRI) gives a more precise evaluation of the quantity, location, and type of fibroids specially in cases with considerable uterine enlargement [6, 7] and submucosal fibroids. Furthermore, MRI can be utilized to differentiate between fibroids and their imitators, such as adenomyosis, ovarian neoplasms, and localized myometrial contractions [8].The introduction of 3D ultrasound in evaluating uterine fibroids appears to be an upcoming and promising prospect [9]. However, the evidence on the role of Three-Dimensional Ultrasonography for fibroid mapping is quite limited up till now.

3) Aim of the study The aim of this study is to compare the accuracy of 3D ultrasound and MRI for fibroid mapping in women with symptomatic fibroids diagnosed by 2D ultrasound.

4) Subjects and Methods

1. Study type: Cross sectional observational study

2. Inclusion criteria:

   • Age group: child bearing period.

   • Abnormal uterine bleeding

   • Dysmenorrhea
   • Pressure symptoms
   • Infertility
   • Pregnancy loss

3. Exclusion criteria

   • The cardiac implantable electronic device (CIED)
   • Metallic intraocular foreign bodies
   • Implantable neurostimulation systems
   • Cochlear implants/ear implant
   • Drug infusion pumps
   • Cerebral artery aneurysm clips
   • Magnetic dental implants
   • Artificial limb

4. Methods

   • This study is a clinical trial that will include all patients fulfilling the eligibility criteria and presented to the department of Obstetrics and Gynecology in Sohag University hospital (Egyptian tertiary referral hospital) from August 2022 to July 2023. The attending physician will explain the nature of the study and all patients will be asked to sign an informed consent. All patients underwent gynecologic and ultrasound examinations, comprising standard 2D followed by 3D ultrasound. For both examinations, a transabdominal and transvaginal US (Voluson,p8) will be used. All symptomatic patients who are diagnosed by conventional 2D scan will be subjected to 3D ultrasound in the mid-cyclic period (late follicular phase) and all the following points will be assessed for fibroid mapping.

     o Uterine corpus: Measurement of length, anteroposterior diameter, transverse diameter and volume

     o Serosal contour: Regular versus lobulated

     o Myometrial walls: Symmetrical versus asymmetrical

     o Myometrial echogenicity: Homogeneous versus heterogeneous

     o Myometrial lesions Well defined versus ill defined Number Location (anterior, posterior, fundal, right or left lateral, global) Site (type according to FIGO classification) Size (three perpendicular diameters) Outer lesion-free margin (distance from the serosal surface) Inner lesion-free margin (distance from the endometrial surface) Echogenicity (homogeneous versus heterogeneous; hypo-, iso-, hyper-echogenic)

   • Sonographic evaluation will be done by the same gynecologist to avoid interpersonal variability.

   Then all the patients will be subjected pelvic MRI at the radiology department in Sohag University hospital and all cases will be evaluated by the same radiologist using the proper MRI protocol including multiplanar T2-weighted sequences and pre-contrast T1-weighted imaging in either the sagittal or axial plane. Then we will compare the 3D ultrasonographic evaluation and the MRI fibroid mapping with the definite intraoperative findings and retrospectively evaluate the impact of this evaluation on the selected surgical intervention.

5. Diagnosis of Fibroids by 3D-ultrasonography • This technology captures serial consecutive 2D pictures in three planes: axial, horizontal, and perpendicular. The 2D slice thickness, which may be modified in increments of 2, 4, or 8 mm depending on the individual needs of each investigation, is then translated into volume data, which can subsequently be saved and analyzed in various angles and arbitrary planes[10] . 3D US also offers an accurate coronal view of the uterus, which aids in the delineation of fibroid extension inside the myometrium and into the endometrial cavity. It also depicts the extent and grade of cavity distortion.

3) Outcome measures:

1. Primary

   • The sensitivity and specificity of the 3D-Ultrasonography and MRI for the mapping of different types of symptomatic uterine fibroids according to the final intraoperative diagnosis.

2. Secondary • The validity of 3D-ultrasonography and MRI of Fibroids for selecting the appropriate way of management.

5) Statistical analysis: This is a cross sectional study that will include all eligible patients from August 2022 to July 2023. Case by case analysis will be done to test the sensitivity and specificity of each 3D ultrasonographic marker and MRI for fibroid mapping in comparison to final intraoperative findings. Data will be expressed as mean ± standard deviation (SD), unless stated otherwise. Chi-squared test will be used to compare categorical variables and Student's t-test to compare continuous variables. A p-value of <0.05 will be considered statistically significant. STATA v14 (StataCorp. 2015. Stata Statistical Software: Release 14. College Station, TX: StataCorp LP) and MedCalc programs and will be used for data analysis.

Inclusion Criteria:

• • Age group: child bearing period.

  • Abnormal uterine bleeding
  • Dysmenorrhea
  • Pressure symptoms
  • Infertility
  • Pregnancy loss

Exclusion Criteria:

• • The cardiac implantable electronic device (CIED)

  • Metallic intraocular foreign bodies
  • Implantable neurostimulation systems
  • Cochlear implants/ear implant
  • Drug infusion pumps
  • Cerebral artery aneurysm clips
  • Magnetic dental implants
  • Artificial limb

• Age group: child bearing period.
• Abnormal uterine bleeding
• Dysmenorrhea
• Pressure symptoms
• Infertility
• Pregnancy loss