Abstract
Article: Prefrontal Space Ratio—A Novel Ultrasound Marker in the Second Trimester Screening for Trisomy 21: Systematic Review and Meta-Analysis
Authors: Mohammad Zare Mehrjardi, MD, and Elham Keshavarz, MD
Category: Obstetrics [OB]
Credit: 1.0 SDMS CME Credit
Objectives: After studying the article entitled “Prefrontal Space Ratio—A Novel Ultrasound Marker in the Second Trimester Screening for Trisomy 21: Systematic Review and Meta-Analysis,” you will be able to:
Describe the value of prefrontal space ratio as a soft marker in the second trimester screening for trisomy 21
Explain the prefrontal space ratio measurement methods
Discuss the advantages of including a prefrontal space ratio assessment to increase the detection rate of aneuploidies and reducing the false-positive rate
In which fetal situation are soft markers more commonly found when performing second trimester sonographic screening on fetuses with predefined structural abnormalities? Aneuploid Euploid Having an exact multiple of the haploid number Having balanced sets of chromosomes
Which of the following are included in the most common facial markers for detecting trisomy 21 fetuses? Nasal bones and nuchal fold thickness Absent nasal bone and maxillary bone length Hyperplastic nasal bone and aberrant right carotid artery Ventriculomegaly and increased nuchal fold thickness
What type of diagnostic testing should be offered to the patient if two major soft markers are present or if the pregnancy falls into the high-risk category? Karyotyping Mosaicism Amniocentesis Quadruple screen
How does the prefrontal space ratio (PSFR) measurement described by Chaveeva et al. differ from the popular method? The measurement is determined by the Length of the mandibulo-maxillary one Length of the second line from the superior end of the skull to the forehead Dividing D1 by D2 Distance between the mandible and maxilla
In the meta-analysis, what was the purpose of including only a random sampling of all ethnicities? Increase the sample population without language restrictions Include both methods of determining the PFSR Decrease mildly skewed standard deviation Decrease the between-study heterogeneity
What factor would affect the final risk assessment results considering the likelihood ratios? Investigating nasal bone length and prefrontal space ratio measurements on the same midsagittal section Finding the average of three nasal bone length and prefrontal space ratio measurements Correlating prefrontal space ratio measurements with gestational age and maternal age Multiplying the positive likelihood ratios attributed to all absent soft markers by the patient baseline risk
How did the results of this meta-analysis on prefrontal space ratio achieve the goal of increasing the detection rate of aneuploidies along with a reduced false-positive rate? DR = 26.0%; FPR = 1.0% DR = 86.2%; FPR = 1.0% DR = 26.0%; FPR = 5.0% DR = 87.2%; FPR = 5.0%
Footnotes