Clinical and ultrasound characteristics of deep endometriosis affecting sacral plexus

Abstract

ObjectivesTo describe sonomorphological changes and appearance of deep endometriosis (DE) affecting the nervous tissue of the sacral plexus (SP).MethodsThis was a retrospective study of symptomatic female patients who underwent radical resection of histologically confirmed DE affecting the SP who had undergone preoperative transvaginal sonography (TVS). Between 2019 and 2023 lesions were described based on the terms and definitions of the International Deep Endometriosis Analysis (IDEA) group. DE affecting the SP was diagnosed on ultrasound by TVS, when sonographic criteria of DE were visualized in conjunction with fibers of the SP and the presence of related symptoms, so‐called sacral radiculopathy. Clinical symptoms, ultrasound features and histological confirmation were analyzed for each patient included.ResultsTwenty‐seven patients with DE infiltrating the sacral plexus were identified in 2 contributing tertiary referral centers. Median age was 37 (range, 29–45) years and all of the patients were symptomatic and presented one or more of the following neurological symptoms: dysaesthesia in the ipsilateral lower extremity (n = 17), paraesthesia in the ipsilateral lower extremity (n = 10), chronic pelvic pain radiating in the ipsilateral lower extremity (n = 9), chronic pain radiating in the pudendal region (n = 8), weakness in the ipsilateral lower extremities (n = 3). All DE lesions affecting the SP were purely solid tumors in the posterior parametrium in direct contact with or infiltrating the S1 and/or S2 and/or S3 and/or S4 roots of the SP. The median of the largest diameter of the DE nodules was 35 mm and echogenicity of the DE nodules was in 86% (n=23) non‐uniform. All but one of them contained hyperechoic areas. The shape of the lesions was in 89% (n=24)irregular. Only one lesion exhibited lobulated form, all other irregular lesion showed spiculated appearance. 74% (n=20) of the nodules gave an acoustic shadow, all of them internal. With color or power Doppler examination 78% (n=21) of the nodules showed no signal (Color Score 1). The remaining 22% (n=6) of the lesions manifested only a minimal color content (Color Score 2).According to pattern recognition, most DE nodules were a purely solid non‐uniform hypoechoic nodule with hyperechoic areas, internal shadows and irregular spiculated contours and poorly vascularized at color/power Doppler examination.ConclusionThe ultrasound finding of a parametrial unilateral solid non‐uniform hypoechoic nodule with hyperechoic areas and possible internal shadowing as well as irregular spiculated contours demonstrating poor vascularization on Doppler examination in proximity or involving the structures of the SP reflects DE affecting these structures.This article is protected by copyright. All rights reserved.