Added Value of Contrast-enhanced US for Evaluation of Female Pelvic Disease.

Since the first application of contrast-enhanced US (CEUS) in the late 1960s, the use of US contrast agents has grown tremendously, and this examination has proved to be a valuable adjunct to diagnostic US for detection and characterization of disease. Also, CEUS has emerged as an excellent option for evaluation of indeterminate lesions that require additional imaging, given its excellent safety profile, including that in patients with end-stage renal disease or allergies to contrast material who are unable to undergo contrast-enhanced CT or MRI. US traditionally has been considered the imaging modality of choice for evaluation of the female pelvis, followed by MRI and rarely fluoroscopy, CT, PET, or angiography. CEUS has the potential to add significant value in imaging gynecologic disease, and indications for its use in the female pelvis are expected to continue evolving. It can aid in evaluation of nonvascular structures, such as assessment of tubal patency, uterine cavity morphology, and pelvic fistulas. CEUS can help characterize poorly vascularized gynecologic tumors or tissues with slow flow by using qualitative and quantitative parameters and aid in image-guided interventions or biopsies by facilitating visualization of lesions that are difficult to see with other imaging modalities. The authors provide an overview of current applications of US contrast agents in the female pelvis and discuss associated factors such as technique, interpretation, and image optimization. They also discuss the limitations of CEUS and describe its utility in the evaluation of female pelvic disease by using an organ system case-based approach. © RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Doppler Ultrasound of the Renal Vasculature.

Ultrasound is the first-line imaging modality used in patients with suspected renovascular disease. Common indications include renovascular hypertension and unexplained renal dysfunction. We review the ultrasound imaging findings of various pathologies involving the renal vessels, including the renal arteries (atherosclerotic stenosis, fibromuscular dysplasia, dissection, arteriovenous fistula, and aneurysm) and veins (tumor and bland thrombus as well as vascular compression syndromes). The current role of renal artery stent placement for atherosclerotic stenosis is also discussed.

Distribution of Normative Percentiles of Liver Stiffness Measurement Using Ultrasound Shear Wave Elastography in an Adult Asian Indian Population.

Objective The aim of this study was to determine the normative percentiles for liver stiffness measurement (LSM) using shear wave elastography in an adult Asian Indian population as part of the preventive radiology initiative of the Indian Radiological and Imaging Association (IRIA). Methods LSMs were ascertained by two-dimensional (2D) shear wave elastography using the Mindray Resona series of ultrasound machines. The image quality was assessed using the motion stability index (M-STB) and reliability (RLB) map. Ten acquisitions were documented, and an interquartile range-to-median (IQR/M) ratio ≤30% kilopascal (kPa) units was considered a good-quality measurement. A subgroup of the study population without comorbidities was chosen to derive the normative percentile distribution of LSM using a generalized least squares multivariable fractional polynomial regression model that adjusted for sex and body mass index (BMI). The effectiveness of the estimated percentiles was assessed on the entire study population using the greater than 90th percentile value of the LSM as the cutoff for abnormality. Results The study included 852 people who underwent shear wave elastography from June 2022 to July 2023. The magnitude of compensated advanced chronic liver disease (cACLD) and clinically significant portal hypertension (CSPH) was 6.81% (95% confidence interval [CI]: 5.30-8.7) and 4.91% (95% CI: 3.67-6.60), respectively. The normative percentiles were estimated from 282 persons without associated comorbidity and risk factors. The mean age (standard deviation [SD]) of the normal individuals was 40.90 ± 12.92 years, and 210 (71.47%) were males. The mean age (SD) of the 570 persons excluded from the normative percentiles analysis was 47.94 (12.49) years and 72.11% were males. The sex- and BMI-adjusted age-specific 90th percentiles of LSM were 8.76, 8.78, 8.96, 8.97, 9.25, and 9.45 kPa for 18 to 20, 21 to 30, 31 to 40, 41 to 50, 51 to 60, and 61 to 70 years, respectively. Conclusion The sex- and BMI-adjusted age-specific 90th percentiles for LSM using shear wave elastography in Asian Indian adults are almost similar to the greater than 9 kPa cutoff proposed by the Society of Radiologists in Ultrasound Liver Elastography Consensus Statement guidelines to discriminate cACLD and CSPH from normal individuals.

Multicystic Dysplastic Kidney Disease: An In-Utero Diagnosis.

Multicystic dysplastic kidney (MCDK) is a congenital cystic kidney disease that can be incidentally seen during the antenatal ultrasound. The condition is most commonly asymptomatic. The clinical presentation is usually characterized by multiple small cysts or a single dominating cyst in the fetal kidney depending on the type of MCDK. Most cases undergo spontaneous involution, and complications like hypertension, infection, and malignancy are rare. We present the case of a young Primigravida who was diagnosed to have a fetus with unilateral MCDK in the second trimester and further followed up later in pregnancy as well as four months postnatally. The pregnancy was unremarkable, but for the diagnosis of MCDK in the second trimester; the infant was doing well at the four-month follow-up. Pre-natal ultrasound and MRI are able to diagnose MCDK reliably. Conservative management and follow-up is currently the most common protocol used to manage MCDK.

Novel Consensus Splice Site Pathogenic Variation in THOC2 Gene Leads to Recurrent Arthrogryposis Multiplex Congenita Phenotype: A Case Report.

The THOC2 gene encodes THO complex subunit 2, a subunit of the Transcription-Export (TREX) complex which binds specifically to splice messenger ribonucleic acid (mRNAs) to facilitate mRNA export. Mutations in the THOC2 gene have been described to lead to X-linked mental retardation syndrome type 12/35 (XLMR-12/35) (MIM#300957). Here, we describe for the first time a recurrent arthrogryposis multiplex congenita phenotype (AMC) in two male fetuses in a family. Exome sequencing identified a novel pathogenic variation chrX: 122761817_122761820delTGAC (genome assembly GRCh37 format) or c.2482-1_2484delGTCA (as per Genbank transcript ID NM_001081550) in theTHOC2 gene. This variant affects the consensus acceptor splice site between intron 22 and exon 23. This is the most severe phenotype described in THOC2 gene-related disease till date. This case report expands the clinical phenotype of THOC2 gene related defects.

Infantile Hemangioendothelioma of the Parotid Gland.

A 4-month-old infant presented with a painless swelling overlying the left angle of mandible. Ultrasound and magnetic resonance imaging (MRI) revealed a large lesion replacing the entire left parotid gland, with multiple enlarged vessels. Homogeneous enhancement of the lesion was seen on the postcontrast MRI scans. Based on the imaging features, a diagnosis of infantile hemangioendothelioma of the parotid gland was offered. This helped in avoiding any further invasive testing.