case report

Quantitative Image Analysis for Detecting into the Myometrium of the Placenta Accreta Spectrum: A Case Report

K Kikuchi1, R Oyama2*, T Sato2, H Otsuka2, S Hosomi2, M Terata2,  H Kawamura2, G Haba2, C Isurugi2, T Baba2

1Department of Obstetrics and Gynecology, Iwate Prefectural Ninohe Hospital, Iwate, Japan

2Department of Obstetrics and Gynecology, Iwate Medical University, Iwate, Japan

*Corresponding author: Rie Oyama, Department of Obstetrics and Gynecology, Iwate Medical University, Iwate, Japan

Received Date: 08 February 2023

Accepted Date: 14 February 2023

Published Date: 16 February 2023

Citation: Kikuchi K, Oyama R, Sato T, Otsuka H, Hosomi S, et al. (2023) Quantitative Image Analysis for Detecting into the Myometrium of the Placenta Accreta Spectrum: A Case Report. Gynecol Obstet Open Acc 7: 156. DOI: https://doi.org/10.29011/2577-2236.100156

Abstract

In this study, we investigated intrauterine observations of the placenta accreta spectrum (PAS), and image analysis of blood flow at the site of placental attachment using ultrasound images and open-source image processing software. This report analyzes preoperative images of uteruses using medical image processing software to detect placental vessels antimining the uterine wall. This process allowed us to quantify the blood flow through the myometrium, for application for our PAS patient.

Keywords: MRI; Placenta Accrete Spectrum; Quantitative Image Analysis

Introduction

Placenta accrete spectrum (PAS) is an abnormal trophoblast invasion where part of the placenta lodges too deeply into the myometrium of the uterine wall [1]. In 2015, the American College of Obstetrics and Gynecologists (ACOG), together with the Society for Maternal-Fetal Medicine, built a standardized riskappropriate maternal care facility system, based on the region and expertise of the medical staff, to reduce overall maternal morbidity and mortality from PAS in the United States [2]. Placenta accrete spectrum (PAS) occurs in 3% of women diagnosed with placenta Previa with no history of cesarean deliveries. In the case of placenta Previa in a woman with a history of one or more previous cesarean deliveries, the likelihood of getting PAS dramatically increases. The risk of getting PAS is 3% after one cesarean delivery. This risk increases to 11%, 40%, and 61% after the second, third, and fourth + cesarean, respectively [3,4]. In this study, we encountered 123 cases of placenta Previa, 18 (14.6%) of which turned into PAS in our prenatal maternal care unit over the course of 12 years, and 13 (72.2%) of which were complicated by massive bleeding. Prior to cesarean section, we examined placenta Previa using color flow Doppler ultrasound and magnetic resonance imaging (MRI) to estimate the relationship between the placenta and myometrium of the uterus, and to predict blood volume during surgery. This report analyzes preoperative images of uteruses using medical image processing software to detect placental vessels antimining the uterine wall.

Case Presentation

Case: A 37-year-old, 36+0 weeks pregnant woman presented with placenta Previa. She had given birth via cesarean section twice before. We performed a selective cesarean section, but the placenta could not be removed from the uterine wall; therefore, we performed an emergency hysterectomy. The infant was male, weighing 2344 g, with Apgar scores of 8 points at 1 min, and 9 points at 5 min.

Methods

Image

Step-1: Ultrasound

A pregnant woman was examined using three-dimensional (3D) ultrasound (Voluson E10; GE Healthcare) with a C1-6-D trans-abdominal probe. High-definition and radiant flow methods were used to visualize the placental vessels bridging the placenta to the uterine margin.

Step-2: MRI

We conducted an MRI to confirm the diagnosis was correct, and to determine the depth of invasion and vasculature in the myometrium using 1.5 Tesla MRI (GE MEDICAL SYSTEM). The imaging conditions were T2-weighted FIESTA, with a slice size of 8 mm.

Step-3: Quantitative image analysis

Images obtained from MRI that import into the open-source medical image processing software ‘Image J’ 2.0.0-rc69/1.52p (developed by the National Institutes of Health (NIH)) were used to identify the image analysis ROI. The myometrium at the placental attachment, located near the bladder, was divided into three layers (upper, middle, and deep), that created a gray value distribution for each layer of the myometrium. We measured each layer to express the peak gray value (blood flow region).

Pipeline: To analysis of MRI.

  1. Save the image to HD as DICOM.
  2. Import to Image J 2.0.0-rc69/1.52p.
  3. Re-identify the image analysis location (red line) on Image J.
  4. Measure the brightness distribution of the attached placenta on the myometrium into the myometrium

Results

Ultrasonography: Massive blood flow was observed between the placenta and part of the myometrium, and the blood flowed close to the uterine serosa bladder (Figure 1).

Image analysis: MRI images showed disruption of the zone between the uterus and placenta, and many bright vessels (high signal) in the myometrium were observed using the T2-weighted imaging (Figure 2). Grayscale peak values coincided with the high signal of either invasion or vasculature within the myometrium on MRI-T2 weighted imaging. Peak gray scale value of upper layer of the myometrium was 975.7 (average gray scale value; 730.55) (Figure 3a), middle layer of the myometrium was 416.1 (average gray scale value; 331.38) (Figure 3b), and deep layer of the myometrium was 123.05 (average gray scale value; 98.73) (Figure 3c). The area with abundant blood flow on upper layer of the myometrium showed high values (>600). Areas with moderately high blood flow in the middle layer of the myometrium had median values (250~300). The deep layer of the myometrium showed low values (<80), which meant that there was little to no blood flow to the deep layer. This gray scale value was significantly different between abundant vascular, invasion and poor vascular, or noninvasion within the myometrium.

 

Figure 1: Ultrasound image of placenta accrete spectrum using three-dimensional (3D) high definition-flow with radiant flow method.

 

Figure 2: MRI of placenta accreta spectrum (placenta previa with accreta). a; yellow circle shows the placenta tissue invasion within the myometrium (regular size image). b; red circle shows the area of placenta tissue invasion and vessels (zoomed image).