3D power Doppler in uterine fibroids; influence of gain, cardiac cycle and off-line measurement techniques

Hysteroscopic laser ablation of symptomatic uterine fibroids: insights from a prospective study

OBJECTIVE

This study aimed to evaluate the feasibility and efficacy of in-office hysteroscopic ablation of submucous uterine fibroids using a diode laser.

METHOD

A pilot study was conducted between January 2018 and January 2019 in a tertiary care university hospital. Patients with at least one symptomatic, class 0-2 FIGO classification, uterine fibroid ≤7 cm in size were eligible for inclusion. Evaluation of the changes in fibroid size and vascularity was performed using three-dimensional Doppler ultrasonography. Vaporization of the fibroid core was conducted using a 980-1470 nm wavelength diode laser inserted through the hysteroscope's working channel. The primary outcome was evaluation of the fibroid volume before and at 2 months after the procedure.

RESULTS

Twenty women were enrolled in the study. At 2-month follow-up, the volume of the fibroids was significantly reduced (51.6 ± 22.5 vs. 33.4 ± 17.1 mm3; p < 0.001). A major reduction of three-dimensional sonographic color Doppler vascularity (observed by the same operator and confirmed by four blind reviewers) was also achieved in 12/20 patients (60%; p = 0.03) while a reported symptom of heavy menstrual bleeding decreased from 18/20 (90%) to 2/18 (10%; p < 0.01).

CONCLUSION

Hysteroscopic laser ablation represents a feasible and effective alternative for treating women with symptomatic submucous fibroids in the office setting. Further studies with larger sample size and longer follow-up periods are needed to validate this promising technique.Key messageThis pilot study shows that in-office hysteroscopic laser ablation (HLA) could be a feasible alternative to treat symptomatic submucous uterine fibroids by coagulating their core, reducing their size and vascularization.

Visualisation of microvascular flow in benign uterine disorders: a pilot study of a new diagnostic technique

BACKGROUND

Uterine disorders have clear overlapping symptoms and ultrasound discrimination is not always easy. Accurately measuring vascularity is of diagnostic and prognostic value. Power Doppler is limited to imaging only the larger vessels. Assessment of the microvasculature requires advanced machine settings.

OBJECTIVES

In this pilot study, we aimed to test the feasibility of microvascular flow imaging of benign uterine disorders.

MATERIAL AND METHODS

Two experienced gynaecologists (JH, RL) randomly applied power Doppler and MV-flowTM mode during a single day, in ten patients each visiting the outpatient clinic. Images of eight patients were labelled with a diagnosis by the attending physicians and collected as coded data.

MAIN OUTCOME MEASURES

Microvascular flow images of normal uterine architecture including the fallopian tube, and of benign disorders such as fibroids, adenomyosis, endometriosis and uterine niches were collected. For both Doppler techniques, qualitative descriptive evaluation of the vascular architecture and a quantitative vascular index of fibroids were provided. Finally, we evaluated the effect of the cardiac cycle.

RESULTS

All microvascular flow images showed more distinctive vascular structures than visible on power Doppler. Calculating a vascular index for fibroids on 2D MV-flowTM images was easily performed on-site. During the cardiac cycle a higher vascular index (VI 75.2) is obtained in systole as compared with diastole (VI 44.0).

CONCLUSION

Microvascular flow imaging allowed detailed visualisation of the uterine vascular architecture and is easy to use.

WHAT IS NEW?

Microvascular flow imaging may be of added value for diagnosing uterine disorders, as well as for pre- and post-operative assessment of suited surgical techniques. Yet, validation with histology and clinical outcomes is required.

How to use power Doppler ultrasound in transvaginal assessment of uterine fibroids

Measuring vascularization in uterine fibroids is important for their diagnosis, treatment and prognosis. Vascularization can be measured by power Doppler ultrasound. The power Doppler signal depends on fibroid characteristics and on a variety of ultrasound-machine settings. Literature describing which machine settings influence the power Doppler signal is limited. Each manufacturer names settings and presets at their own discretion, with little information available publicly. Consistency of machine settings is important for correct interpretation of images in daily practice and is essential in yielding reproducible data for research. The aims of this paper, drawing from both a literature search and semistructured interviews with ultrasound-machine engineers and clinical experts in gynecological ultrasound, were: (1) to provide comprehensive background information on ultrasound physics and fibroid characteristics; (2) to present an overview of machine settings relevant to both two- and three-dimensional power Doppler, including power Doppler frequency, pulse repetition frequency, gain, wall-motion filter, acoustic power, persistence and signal rise; and (3) to provide a step-by-step tutorial on the optimal settings for vascular evaluation of uterine fibroids using power Doppler. The step-by-step tutorial comprises six steps to optimize the power Doppler signal, create a preset and acquire a reliable three-dimensional volume. This step-by-step tutorial should help research groups and clinicians to use power Doppler correctly and reproducibly in the evaluation of uterine fibroids. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Ultrasound features of highly vascularized uterine myomas (uterine smooth muscle tumors) and correlation with histopathology

OBJECTIVE

To correlate the ultrasound appearance of highly vascularized uterine myomas with their histopathological diagnosis.

METHODS

This was a prospective observational study of patients with a preoperative ultrasound diagnosis of a highly vascularized uterine myoma (color score of 3 or 4, according to the Morphological Uterus Sonographic Assessment (MUSA) criteria), characterized by circumferential and intralesional vascular pattern, who underwent myomectomy or hysterectomy. For each patient, ultrasound characteristics were recorded at baseline, including the number of lesions, the size, echogenicity and border regularity of the lesion, presence of cystic areas and shadowing within the myoma, and visualization of the endometrium. Ultrasound features were correlated with the definitive histological diagnosis. Ultrasound features were then compared between malignant and benign lesions.

RESULTS

We included 70 patients with highly vascularized uterine myomas on power/color Doppler. Their mean age was 46.5 ± 11.4 years and 13 (18.6%) were postmenopausal. At histological examination, 65 (92.9%) uterine myomas were benign lesions, comprising 32 typical leiomyomas, 29 leiomyoma variants and four adenomyomas. The remaining five (7.1%) uterine myomas were malignant masses, comprising two uterine sarcomas, one leiomyosarcoma, one neuroendocrine tumor and one uterine smooth muscle tumor of uncertain malignant potential (STUMP). The mean age of patients with a malignant lesion was significantly higher than the age of those with a benign lesion (64.8 ± 16.0 vs 42.4 ± 5.1; P < 0.001). Four out of five patients with a malignant lesion were over 45 years old. Ultrasound demonstrated cystic areas within the lesion in 10/32 (31.3%) typical leiomyomas, 16/29 (55.2%) leiomyoma variants, all four adenomyomas and in the cases of STUMP and leiomyosarcoma. Lesion borders were regular in 64/65 (98.5%) benign lesions and 2/5 (40%) malignant lesions (P < 0.05). No significant differences were observed between benign and malignant lesions with respect to echogenicity, presence of shadowing and size. The endometrium was visible in 55/65 women with benign lesions and in 2/5 with malignant lesions (P = 0.03).

CONCLUSIONS

Our results showed that ultrasound features of uterine myomas, such as circumferential and intralesional vascularity, cystic areas and lesion borders, are important parameters for differential diagnosis, especially when combined with the patient's age. Such features could be useful to differentiate typical myomas from benign variants and malignant lesions in a preoperative setting and to select patients that may benefit from conservative management rather than surgery. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Differences in fibroid vascularity after three months of pre-treatment with leuprolide acetate or ulipristal acetate: A pilot study

OBJECTIVES

To investigate differences in volume and fibroid vascularity expressed in vascular index after three months of (pre-)treatment with leuprolide acetate (LPA) or ulipristal acetate (UPA).

STUDY DESIGN

Prospective pilot study of 23 premenopausal women with uterine fibroids. Patients who started with LPA or UPA and had at least one fibroid with a size between 3 and 12 cm, were included consecutively. Per patient one fibroid was evaluated. The ultrasound was performed at baseline and after three months using LPA or UPA using a standardized protocol. 3D scans were evaluated using VOCAL software to calculate outcomes of volume, vascular index (VI) without shell ("shell off") and of the inner shell.

RESULTS

Four patients in the LPA group were additionally excluded from analyses due to insufficient quality of 3D scans. In the ten remaining patients (pre-)treated with LPA both volume and vascular indices of the fibroid reduced significantly after three months from a median of 224.3 cm³ (IQR 338.0) to 124.8 cm³ (IQR 186.1) (p = 0,05); median VI fibroid (shell off) reduced from 4.30 (IQR 4.72) to 0.93 (IQR 1.54) (p = 0,05); and VI inner capsule from 6.34 (IQR 7.51) to 1.28 (IQR 2.13) (p = 0,05). After UPA (n = 9) changes in fibroid volume and vascular indices did not reach statistical significance. Volume reduced from 248.5 cm³ (IQR 271.9) to 140.7 cm³ (IQR 209.4) (p > 0,05); median VI fibroid (shell off) from 2.97 (IQR 3.81) to 2.90 (IQR 4.82) (p > 0,05); and VI inner capsule from 2.56 (IQR 7.48) to 2.89 (IQR 4.83) (p > 0,05). A strong positive correlation was found between the VI of the fibroid (shell off) at baseline with the volume change after three months of LPA use (LPA r = 0.636, p = 0.048, 95% CI = -0.03 - 1.00).

CONCLUSION

In this pilot study we observed a consistent and statistically significant decrease in VI and fibroid volume after three months of LPA treatment in patients with uterine fibroids. The decrease in fibroid volume and VI was less consistent after UPA use. The strong correlation between the VI at baseline and volume reduction, may in theory be used to predict the volume reduction after LPA.

3D Power Doppler vascular indices as a novel technique in assessing the outcome of minimally invasive techniques in uterine fibroids treatment

Uterine fibroids are considered to be the most frequent female benign tumours. The most common reported symptoms of fibroids are heavy menstrual bleeding and painful menstruation, pelvic pain, urinary problems, constipation, as well as infertility and recurrent pregnancy loss. The mainstay of fibroid treatment is surgery, but nowadays minimally-invasive techniques are growing in popularity. Vascularity of fibroids may play a role in the outcome of these techniques, which is why it is important to find an objective, reproducible technique to measure the vascularization before and after the procedure. The 3D Power Doppler vascular indices (3DPDVI) allow objective assessment of vascularization in the entire volume of the tumour. Initially this technique was mostly used in experimental imaging phantoms, but recently many studies focus on the clinical utility of this technique. Power Doppler allows to obtain information on vascularity in the area of interest, while 3DPDVI can be objectively calculated by the Virtual Organ Computer-aided AnaLysis (VOCAL™) software. 3DPDVI showed high reproducibility in most of the studies. This technique has an important role in monitoring the outcome of minimally invasive procedures in fibroid treatment, because they affect vascularity of the tumours. Although there are some limitations of 3DPDVI, it seems that their application may be an effective tool in objective assessment of vascularity of fibroids. However further studies are required to consolidate the usage of 3DPDVI in clinical practice.