OB/GYN Sonography Review Green Davies Book
The arrow labeled A is pointing to the: A. Posterior fossa B. Posterior ridge C. Vallecula D. Anterior fossa E. Tentorium
A, Posterior fossa.
At 5-10 weeks, the secondary yolk sac is considered abnormal if it measures: A. <2mm B. <3mm C. <4mm D. <5mm E. <6mm
A. <2 mm.
The fetal kidneys are most commonly located: A. Adjacent to the fetal spine bilaterally B. At the level and posterior to the fetal diaphragm C. Adjacent and inferior to the cord insertion D. Slightly superior and adjacent to the fetal stomach E. At the level and posterior to the cord insertion
A. Adjacent to the fetal spine bilaterally.
What is the arrow pointing to in this image? A. Amnion B. Yolk sac C. Septum D. Chorion E. Synechiae
A. Amnion.
You obtain this image from a patient with a gestational sac measuring more than 18mm transvaginally. What is this condition called? A. Anembryonic pregnancy B. Fetal demise C. Partial spontaneous abortion D. Complete spontaneous abortion E. Incomplete abortion
A. Anembryonic pregnancy. Explanation: When no embryo is seen within the gestational sac and the mean sac diameter is greater than 18mm transvaginally or 25mm transabdominally, anembryonic pregnancy (also known as blighted ovum) is the most likely cause.
The fetal lung marked with the asterisk is more echogenic than the contralateral lung because of: A. Artifact B. Fetal lung maturity C. Congenital diaphragmic hernia D. Differential blood flow E. Tracheal atresia
A. Artifact. Explanation: Shadowing in the far field makes the contralateral lung less echogenic. The echogenicity of the lungs should never be used to determine fetal lung maturity. Tracheal atresia results in bilaterally increased echogenicity.
Which of the following landmarks should be visualized in the proper axial plane required for both biparietal diameter (BPD) and head circumference (HC)? A. Cavum septi pellucidi B. Cerebellum C. Sylvian fissure D. Orbits E. Pons
A. Cavum septi pellucidi. Explanation: The proper axial plane required for measurement of BPD or HC should include the cavum septi pellucidi, falx cerebri, and thalamic nuclei. The fetal orbits, cerebellum, and pons should not be in this plane.
What is arrow A pointing to in this image? A. Cavum septum pellucidi B. Cisterna magna C. Peduncles D. Cerebellum E. Corpus callosum
A. Cavum septum pellucidi.
The anastomotic network of arteries located at the base of the brain constitutes the: A. Circle of Willis B. Internal carotid arteries C. Sylvian fissure D. Vertebrobasilar circulation E. Posterior cerebral arteries
A. Circle of Willis Explanation: The circle of Willis, located at the base of the brain anterior to the brainstem, is shaped like a traffic circle of blood vessels. In the presence of an obstruction, it serves as a safety mechanism for blood flow through the fetal brain. The circle is formed by the anterior communicating artery, anterior cerebral arteries, posterior communicating arteries, and posterior cerebral arteries. Also shown are the basilar artery, vertebral arteries, the internal carotid arteries, middle cerebral arteries, and ophthalmic arteries.
This image is sometimes obtained to rule out: A. Cleft lip B. Encephalocele C. Gastroschisis D. Hypotelorism E. Cleft palate
A. Cleft lip. Explanation: The most common facial anomalies include the various cleft defects of the lip and palate. This axial view aids greatly in the detection of a median, bilateral, or unilateral cleft lip.
All of the following characteristics suggest an abnormal early pregnancy EXCEPT: A. Fundal implantation B. Dilated cervix C. Poor decidual ring D. Fluid around the sac E. Irregular sac shape
A. Fundal implantation. Explanation: Low implantation or implantation outside the uterine cavity--not fundal implantation--is a sign of an abnormal pregnancy.
What is the arrow pointing to in this image? A. Gallbladder B. Stomach C. Hepatic veins D. Umbilical vein E. Portal vein
A. Gallbladder.
This sagittal transvaginal image demonstrates a normal-appearing intrauterine gestational sac. The hypoechoic structure indicated by the calipers most likely represents: A. Leiomyoma B. Ovary C. Engorged vessel D. Artifact E. Cyst
A. Leiomyoma. Explanation: This longitudinal image demonstrates a leiomyoma (fibroid) as a characteristically well-circumscribed hypoechoic mass.
In this image, the three arrows are pointing to: A. Ossification centers B. Transverse processes C. Interverterbal discs D. Laminae E. Spinal cord
A. Ossification centers.
In the image in question 51, what structure is labeled 2? A. Right ventricle B. Left ventricle C. Right atrium D. Left atrium E. Aorta
A. Right ventricle.
In the image in question 62, the anatomy to which arrow D is pointing is best described as the: A. Right ventricular outflow tract B. Aorta C. Right pulmonary artery D. Right atrium E. Right ventricle
A. Right ventricular outflow tract.
An incomplete abortion is defined as: A. Spontaneous abortion with retained products of conception B. Anembryonic abortion C. Heterotopic pregnancy D. Subchorionic hemorrhage E. Ectopic pregnancy without bleeding
A. Spontaneous abortion with retained products of conception. Explanation: An incomplete abortion is the spontaneous expulsion of some but not all products of conception during the first half of the pregnancy. These patients may or may not have bleeding.
The double bleb sign refers to the sonographic presentation of: A. The amnion and adjacent yolk sac B. A heterotopic pregnancy C. A bicornuate uterus D. The amnion and chorion E. Two intrauterine gestational sacs
A. The amnion and adjacent yolk sac.
In this coronal view of the fetal pelvis, what is the structure labeled 1? A. Urinary bladder B. Small bowel C. Symphysis pubis D. Iliac wing E. Internal iliac arteries
A. Urinary bladder.
Judging from this transverse image of the maternal abdomen, what is the presentation of the fetus? A. Vertex B. Transverse fetal head right C. Transverse fetal head left D. Breech E. Transverse spine up
A. Vertex. Explanation: Fetal presentation refers to the part of the fetus that is expected to be delivered first. It should not be confused with fetal lie, which describes the longitudinal axis of the fetus in relation to the longitudinal axis of the mother. Fetal lie may be longitudinal, transverse, or oblique. Together fetal presentation and fetal lie describe fetal position. Vertex is the cephalic fetal presentation in which the parietal bones are presenting. Among the many other possible fetal positions are those illustrated above.
Up to 10 weeks' gestational (menstrual) age, the mean diameter of the normal gestational sac should grow approximately: A. 0.5mm per day B. 1.0mm per day C. 2.0mm per day D. 3.0mm per day E. 4.0mm per day
B. 1.0mm per day
Prior to 10 weeks, the normal yolk sac diameter measures: A. 1-4mm B. 2-6mm C. 3-5mm D. 4-8mm E. 5-10mm
B. 2-6mm. Explanation: B is the best choice. Prior to 10 weeks, normal ranges for the secondary yolk sac are not less than 2mm and not greater than 6mm; authorities vary, some now saying that the yolk sac measurement should not exceed 7mm. Large, irregularly shaped, and calcified yolk sacs have all been found to correlate with early pregnancy failure.
Normal embryonic midgut hernation occurs at approximately: A. 6 menstrual weeks B. 8 menstrual weeks C. 10 menstrual weeks D. 12 menstrual weeks E. 14 menstrual weeks
B. 8 menstrual weeks. Explanation: Starting at about 8 menstrual weeks the embryonic gut grows rapidly. At this time the abdomen is unable to accommodate the intestinal enlargement, so a normal developmental process known as physiologic (or midgut) herniation occurs in which the bowel herniates into the base of the umbilical cord, giving the appearance of an abdominal wall defect. The intestines will eventually regress into the abdomen.
Which of the following provides important prognostic information about fetal renal function? A. Amniotic fluid volume at 11 menstrual weeks B. Amniotic fluid volume at 15 menstrual weeks C. Amniotic fluid volume at term D. Size of the fetal kidneys E. Shape of the fetal kidneys
B. Amniotic fluid volume at 15 menstrual weeks. Explanation: After 14-15 menstrual weeks, the amniotic fluid volume and fluid in the fetal bladder are almost entirely due to functioning kidneys. Prior to this time, amniotic fluid may be a result of transudation from the placenta and membranes.
In the image in question 62, arrow C is pointing to the: A. Right ventricle B. Aorta C. Right atrium D. Right pulmonary artery E. Right ventricular outflow tract
B. Aorta
In the image in question 56, the bottom arrow is pointing to the: A. Laminae B. Centrum C. Intervertebral disc D. Spinal cord E. Spinous process
B. Centrum. Explanation: This transverse image nicely demonstrates the three ossification centers (arrows) of one vertebra. Two lateral ossification points, the laminae (upper arrows labeled L), are located posterior to the spinal canal. These posterolateral ossification centers should appear parallel or angled toward each other as they do in the image. The third ossification center, the centrum (lower arrow labeled C), lies anterior to the spinal canal.
The small, rounded echogenic structure within the left ventricle of this fetal heart is seen at the level of the: A. Ventricular septum B. Chordae tendineae/papillary muscle C. Foramen ovale D. Aortic semilunar valve E. Mitral valve
B. Chordae tendinaeae/papillary muscle. Explanation: Echogenic foci may be seen in either ventricle. These foci most often correspond to the moderator band in the right ventricle and/or the papillary muscle or chordae tendineae in either ventricle.
Of the following methods of calculating an estimated date of confinement (EDC), which is the most reliable? A. Fundal height of uterus B. Crown-rump length C. First sign of quickening D. Sac measurement E. Mcdonald measurement
B. Crown-rump length Explanation: The estimated date of confinement (EDC) is also known as the expected date of delivery or estimated due date (EDD). Crown-rump length measurements taken within the first 10 weeks of pregnancy are typically used to calculate the EDC.
According to the practice guidelines of the American Institute of Ultrasound in Medicine (AIUM), a basic fetal scan does NOT require imaging of the: A. Four fetal extremities B. Fetal hands and feet C. Four-chamber view of heart D. Three vessel cord E. Umbilical cord insertion into fetal abdomen
B. Fetal hands and feet.
A successful pregnancy outcome is associated with a yolk sac that: A. Occupies more than 30% of gestational sac volume B. Has a round shape C. Measures less than 2mm in diameter at 8-10 weeks D. Measures greater than 6mm in diameter E. Has irregular echogenic borders
B. Has a round shape. Explanation: The normal yolk sac has a diameter between 2mm and 6mm and is round. A small, absent, misshapen, or calcified yolk sac is associated with a poor prognosis. A yolk sac that is disproportionately large in relation to the gestational sac also suggests an abnormal early pregnancy.
Your patient is 10 weeks by good menstrual dates but presents with pregnancy induced hypertension. You should suspect: A. An embryonic pregnancy B. Hydatidiform mole C. Threatened abortion D. Ectopic pregnancy E. Normal pregnancy
B. Hydatidiform mole. Explanation: In most cases, pregnancy-induced hypertension--blood pressure exceeding 140/90--does not present until the second trimester. When accompanied by clinical findings of proteinuria, excessive maternal weight gain, and generalized edema, PIH is also known as pre-eclampsia, a term some authorities prefer over PIH. When pre-eclampsia occurs in the first trimester it is almost always pathognomonic of a molar pregnancy. Pre-eclampsia is the most common maternal complication of pregnancy.
This patient presented with bleeding and cramping. Her pregnancy test is weakly positive. Three days prior, a living IUP was documented in the uterus. This transvaginal image suggests: A. Normal uterine pregnancy B. Incomplete abortion C. Ectopic pregnancy D. Pseudocyesis E. Placental abruption
B. Incomplete abortion. Explanation: Given the patient's history the most likely diagnosis is incomplete abortion. The uterus contains tissue but shows nothing that represents a normal pregnancy. An ectopic pregnancy may show fluid within the endometrial cavity if there is rupture of the fallopian tube. Pseudocyesis will appear as a normal, nongravid uterus. Molar tissue usually shows multiple cystic areas representative of hydropic changes within the placenta.
Normally, the anatomic structure closes to the spine in a four-chamber view of the fetal heart is the: A. Left ventricle B. Left atrium C. Right ventricle D. Right atrium E. Apex
B. Left atrium.
What structure is labeled 1 in this image? A. Right ventricle B. Left ventricle C. Right atrium D. Left atrium E. Univentricle
B. Left ventricle.
Which of these drugs may be used to treat an early unruptured ectopic pregnancy in order to preserve fertility? A. Pergonal B. Methotrexate C. Diethylstilbestrol (DES) D. Thalidomide E. Danazol
B. Methotrexate. Explanation: Methotrexate is a folic acid antagonist used as an antineoplastic agent. It is also used in the treatment of psoriasis.
What is the arrow pointing to in this transverse image through the fetal abdomen? A. Multicystic kidneys B. Normal kidneys C. Polycystic kidneys D. Hydronephrotic kidneys E. Pseudo kidney masses
B. Normal kidneys.
The bladder of the male fetus is sometimes enlarged because of: A. Hypospadias B. Posterior urethral valves C. Imperforate hymen D. Ureteropelvic junction E. Ectopic ureterocele
B. Posterior urethral valves. Explanation: A posterior urethral valve, which obstructs the posterior urethra, is the most common cause of bladder outlet obstruction in the male fetus. The sonographic presentation includes a persistent and oftentimes profoundly dilated bladder or thickened bladder walls. Distention of the posterior urethra is sometimes visualized, and moderate to severe oligohydramnios may be present when the obstruction affects the fetus's ability to void into the amniotic sac, as is often the case. Although obstruction of the bladder outlet mainly affects the male fetus, the female fetus also may suffer from the urethral obstruction secondary to a number of pathologies. In the female, the most common cause of urethral obstruction is clocal malformation or urethral atresia.
In the image in question 86, what is the structure labeled 2? A. Urinary bladder B. Small bowel C. Symphysis pubis D. Iliac wing E. Internal iliac arteries
B. Small bowel.
Which statement about ectopic pregnancies is NOT true? A. Interstitial ectopics are more serious than those located in the ampulla. B. The ovary is the second most common site for ectopic pregnancy. C. The increased incidence of ectopic pregnancies is mostly attributable to sexually transmitted diseases. D. The most common clinical symptom is pain. E. If a patient has had a previous ectopic pregnancy, she is at increased risk for a recurrent ectopic pregnancy.
B. The ovary is the second most common site for ectopic pregnancy. Explanation: The ovary is NOT a common site for ectopic pregnancy. Approximately 92-97% of ectopic gestations occur in the fallopian tubes. Between 2.0% and 2.5% of ectopic pregnancies are interstitial within the uterine cornua. Other ectopic implantation sites are nontubal and may uncommonly occur in the ovaries, the cervix, and the abdomen.
Longitudinal and transverse views of the fetal spine are a routine part of the fetal exam. When the normal fetal spine is imaged transversely, the sonogram demonstrates what? A. Three ossification center, two posterior and one anterior, with the two posterior centers pointing away from each other. B. Three ossification centers, two posterior and one anterior, with the two posterior pointing toward each other. C. Three ossification centers, two anterior and one posterior, with the two anterior centers pointing towards each other. D. Three ossification centers positioned an equal distance apart and splaying outward at the level of the sacrum.. E. Three ossification centers positioned an equal distance apart and tapering toward the sacrum.
B. Three ossification centers, two posterior and one anterior, with the two posterior pointing toward each other.
Which statement about fetal brain anatomy is TRUE? A. The cavum septi pellucidi is seen in the posterior fossa. B. Ventricular measurements are consistent throughout the second and third trimesters. C. Cerebral peduncles are at the level of the ventricles. D. BPD and head circumference measurements are taken at the level of the cerebellum. E. The choroid plexus sits within the anterior horn of the lateral ventricles.
B. Ventricular measurements are consistent throughout the second and third trimesters.
To differentiate an early intrauterine pregnancy from a pseudogestational sac, it helps to visualize the: A. Decidualized endometrium B. Yolk sac C. Vitelline duct D. Corpus luteum cyst E. Chorionic villi
B. Yolk sac. Explanation: Visualization of the (secondary) yolk sac will distinguish a true gestational sac from a pseudosac.
Sonographically, fetal gender cannot be anatomically differentiated until what gestation age? A. 10 weeks B. 13 weeks C. 16 weeks D. 20 weeks E. 23 weeks
C. 16 weeks. Explanation: Gender identification is not a required part of the basic scan but is often requested by parents. Gender can sometimes be determined as early as 12 weeks using enhanced imaging resolution and Doppler techniques, but misidentification is more likely to occur before 16 weeks since gender determination is not complete until this time and it is easier to misidentify anatomy. Many mothers and fathers develop a strong bond based on fetal gender when that information is provided. When a mistake is made, the emotional effect can be quite devastating.
Normally, nuchal translucency does not exceed: A. 1.5mm B. 2.0mm C. 2.5mm D. 3.0mm E. 3.5mm
C. 2.5mm Explanation: Nuchal translucency--a collection of lymphatic fluid found in the posterior neck region of the embryo--is considered a normal finding during the first trimester if it does not exceed 2.5mm. The measurement is made in the sagittal plane and should be limited to the translucent area only, with the digital calipers placed placed on the inner boundaries at the translucency's widest dimension. The measurement is made between weeks 11 and 14; after this period the lymphatic system has developed sufficiently to drain the area. A nuchal translucency exceeding 3mm is associated with a significantly increased incidence of aneuploidy (abnormal karyotype). The abnormality most commonly associated with increased nuchal translucency is trisomy 21 (Down syndrome). The nuchal translucency measurement should not be confused with the measurement of nuchal fold thickness.
Approximately what percentage of fetal blood flows across the foramen ovale into the left atrium? A. 20% B. 30% C. 40% D. 60% E. 80%
C. 40%.
A longitudinal image shows an intrauterine gestational sac that occupies one-half of the endometrial canal. The sac size indicates that the gestational age of the pregnancy should be: A. 4 weeks B. 6 weeks C. 8 weeks D. 10 weeks E. 12 weeks
C. 8 weeks. Explanation: At approximately 8 weeks' gestation the gestational sac should fill half of the endometrial canal.
In this transvaginal image of a gestational sac, what is the abnormal finding? A. Molar changes in the placenta B. Abdominal wall defect C. Abnormal yolk sac D. Embryonic hydrocephalus E. Theca-lutein cyst
C. Abnormal yolk sac. Explanation: The gestational sac and embryo appear normal for the stage of pregnancy; however, the yolk sac should not be so large in relation to the embryonic pole.
Which view best demonstrates the diaphragm? A. Oblique to the fetus's left B. Transverse C. Coronal D. Oblique to the fetus's right E. Four chamber view of the heart
C. Coronal. Explanation: Both coronal and parasagittal views often allow one to image the diaphragm. This coronal section of a 20-week fetus demonstrates the comparative echogenicity of the liver, the diaphragm, and the lung.
What is being measured in the image in question 7? A. Gestational sac B. Biparietal diameter C. Crown-rump length D. Embryonic disc E. Abdominal circumference
C. Crown-rump length. Explanation: Between 7 and 10 weeks, the crown-rump length is the most accurate measurement of menstrual age. It is measured between the rostral (crown) and caudal (rump) ends of the embryo. The AIUM, in its ob/gyn practice guideline, defines "first trimester" as the pregnancy up to 13 weeks, 6 days. AIUM states that in the first trimester crown-rump measurement is the most accurate means for sonographic dating of pregnancy. It is important to note, however, that spinal segmentation occurs at 11 weeks, which gives the fetus the ability to curl. If the CRL is taken when the fetus is curled up, not stretched out, it will not be accurate. You can measure CRL after 10 weeks must be careful to avoid measuring the curled fetus or accuracy will be affected.
Your patient has a positive pregnancy test and presents with bleeding and cramping. Of the following sonographic findings, which one would make you suspect an impending inevitable abortion? A. Poor decidual reaction B. Double yolk sac C. Dilated cervix D. Low implantation E. Irregular sac shape
C. Dilated cervix Explanation: The best choice is dilated cervix. A lowly implanted sac may or may not abort even if other signs may indicate a failed pregnancy. Once the cervix dilates, abortion will occur. Cervical dilation is determined by observing and measuring for shortening of the cervix. The cervix shortens as dilatation occurs; then funneling of the sac into the dilated portion of the cervical canal begins.
Which of the following is NOT an indication of ectopic pregnancy? A. Fluid in the cul-de-sac B. Adnexal mass C. Double decidual ring D. Fluid within the endometrial cavity E. Fluid in the right upper quadrant
C. Double decidual ring. Explanation: Identification of the double decidual ring (or double decidual sac sign) is the sonographic criterion for determining whether there is a normal intrauterine gestational sac or just endometrial fluid surrounded by a decidualized endometrium. As the use of high-resolution transvaginal sonography has become more extensive, the double sac sign has come to play a less significant role in the diagnosis of pregnancy.
The fluid filled stomach should always be visualized in the fetal left upper quadrant . If it is not seen during the duration of the exam, one should suspect: A. Pyloric stenosis B. Duodenal atresia C. Esophageal atresia D. Jejunoileal obstruction E. Ulcerative colitis
C. Esophageal atresia. Explanation: Visualization of the fluid-filled fetal stomach is an important part of the basic scan. The fetal stomach should be seen filled with fluid during the course of an exam.
In a ruptured ectopic pregnancy, which section of the fallopian tube is potentially the most life-threatening? A. Ligamentous B. Ampulla C. Interstitial D. Fimbrial E. Isthmic
C. Interstitial. Explanation: Interstitial implantation is very rare but very dangerous, because rupture is accompanied by bleeding from uterine arteries. This type of ectopic pregnancy (also known as cornual ectopic pregnancy) may be relatively asymptomatic and can progress without rupture up to 3-4 months.
In the image in question 54, the top two arrows are pointing to the: A. Spinous process B. Intervertebral disc C. Laminae D. Spinal cord E. Centrum
C. Laminae.
Your patient relates a history of amenorrhea for 7 weeks. Her home pregnancy test was negative, but her serum beta-hCG exceeds 4000 mIU/ml. What does the image below demonstrate? A. Pseudocyesis with an endometrial cyst B. Fluid contained within the endometrial cavity C. Normal early intrauterine pregnancy D. Degenerating submucosal fibroid E. Normal empty uterus with periovulatory endometrium
C. Normal early intrauterine pregnancy. Explanation: The image demonstrates a normal intrauterine pregnancy, with the calipers measuring crown-rump length. Clinical signs of pregnancy include a missed menstrual period, nausea, vomiting, malaise, breast tenderness, and on physical examination a gravid uterus (enlarged on bimanual examination). Lab values will detect a positive early pregnancy factor (EPF) and elevated levels of human chorionic gonadotrophin (beta subunit, beta-hCG). Other physical indications include Chadwick's sign (a bluish discoloration of the cervix at 8-10 weeks), Goodell's sign (softening of the vaginal portion of the cervix), Hegar's sign (softening of the uterine isthmus), and hyperpigmentation of the linea alba.
What is the arrow in this image of a 10-week fetus pointing to? A. Umbilical vein thrombosis B. Single umbilical vein C. Normal embryonic midgut herniation D. Omphalocele E. Gastroschisis
C. Normal embryonic midgut herniation. Explanation: Physiologic (or "midgut") herniation of the fetal bowel is part of a normal process of bowel growth and rotation.
If the image in question 74 were taken longitudinally, the fetal lie would be: A. Breech B. Vertex C. Transverse fetal head right D. Transverse spine up E. Transverse fetal head left
C. Transverse fetal head right.
In the image in question 97, the arrow labeled B points to the: A. Aortic semilunar valve B. Mitral valve C. Tricuspid valve D. Pulmonary semilunar valve E. Ventricular septum
C. Tricuspid valve.
Physiologic herniation of fetal intestine outside the fetal abdomen is usually not seen after which gestational age? A. 6-8 weeks B. 8-10 weeks C. 10-12 weeks D. 12-14 weeks E. 14-16 weeks
D. 12-14 weeks. Explanation: Physiologic or midgut herniation is a normal development event that may be confused with true abdominal wall defects. The fetal small bowel develops so rapidly from gestation weeks 9 to 10 that the abdominal cavity cannot contain it. Fetal bowel protrudes into the base of the umbilical cord starting at 8 weeks' gestation, peaking at 9-10 weeks' gestation, and resolving by the 11-12 weeks of gestation as it retracts back into the intra-abdominal cavity.
The lateral ventricle of the fetal brain normally measures: A. 1cm in the largest dimension longitudinally B. 1mm in the largest dimension longitudinally C. 1mm in the largest dimension transversely D. 1cm in the largest dimension transversely E. A and B
D. 1cm in the largest dimension transversely.
Which of the following procedures would be performed to treat the incompetent cervix? A. McDonald procedure B. Shirodkar cerclage C. Cone procedure D. A and B E. A and C
D. A (McDonald procedure) and B (Shirodkar cerclage). Explanation: Shirodkar cerclage is the more complicated of these two procedures. With Shirodkar, the suture is almost completely buried beneath the cervical mucosa. It can be left in place for subsequent pregnancies if a cesarean section is performed. The McDonald procedure is simpler--a purse-string suture of the cervix. The McDonald procedure subjects the cervix to less trauma and produces less blood loss than the Shirodkar procedure.
The image in Question 20 shows the uterine position to be: A. Unidentifiable B. Retroflexed C. Dextroposed D. Anteflexed E. Levoposed
D. Anteflexed. Explanation: The uterus typically lies along the pelvic midline with the uterine corpus and is tilted anteriorly at the cervix. This normal orientation is called anteflexion, and the angle formed between the uterine corpus and the cervix is acute; that is, ordinarily this angle is no greater than 90 degrees.
When do the fetal kidneys begin to develop? A. End of the 7th menstrual week B. Beginning of the 7th menstrual week C. End of the 6th menstrual week D. Beginning of the 6th menstrual week E. Beginning of the 5th menstrual week
D. Beginning of the 6th menstrual week. Explanation: The fetal kidneys begin development at 6 menstrual weeks as the pronephroi, and they are completely formed by week 11 after the metanephroi have ascended into the abdomen.
What is a heterotopic pregnancy? A. A cervical ectopic pregnancy B. A fertility-assisted pregnancy C. An abdominal ectopic pregnancy D. Coexisting intrauterine and ectopic pregnancies E. A twin ectopic pregnancy
D. Coexisting intrauterine and ectopic pregnancies. Explanation: If one can identify a normal intrauterine pregnancy, the likelihood of the patient having an ectopic pregnancy is negligible. However, fertility assistance has caused a slight increase in the incidence of heterotopic ectopic pregnancies, so it is important to remember that a normal IUP does not rule out ectopic pregnancy. The risk of heterotopic pregnancy in the general population is between 1:4000 and 1:30,000; in those undergoing assisted reproductive protocols, the risk is 1:2600.
Second trimester obstetric ultrasound examinations are better than first trimester sonograms in determining? A. Gestational age of fetus B. Fetal life C. Fetal birth weight at term D. Fetal anatomy E. Fetal position
D. Fetal anatomy.
In a fetal heart, what is the name for the normal communication between the right and left atria? A. Atrial orfice B. Atrial septal defect C. Ventricular septal defect D. Foramen ovale E. Atrial meatus
D. Foramen ovale. Explanation: The foramen ovale (top arrow) is a normal opening in the atrial septum that closes after birth. In the right atrium of the fetal heart, the eustachian valve and the crista dividens channel blood toward the foramen ovale, which redirects it to the left atrium, arway from the right. This is the first shunting of blood away from the lungs.
In the image in question 86, what is the structure labeled 3? A. Urinary bladder B. Small bowel C. Symphysis pubis D. Iliac wing E. Internal iliac arteries
D. Iliac wing. Explanation: The image demonstrates the normal fetal pelvic anatomy in a coronal view at the level of the fetal urinary bladder. The iliac wing, small bowel, and bladder are demonstrated in this section. An axial oblique section would demonstrate the symphysis pubis and internal iliac arteries.
Which of the following findings does NOT suggest a spontaneously aborted pregnancy? A. Irregularly shaped gestational sac containing complex echogenic material B. Heavy bleeding and cramping with clots C. Rapidly falling beta-hCG levels D. Large, empty gestational sac E. Empty uterus with thickened endometrium
D. Large, empty gestational sac Explanation: Failure to visualize an embryo within the gestational sac when the mean sac diameter is greater than 25mm transabdominally or greater than 18mm transvaginally is a sign of an anembryonic pregnancy, or "blighted ovum". This is a failed pregnancy rather than a spontaneous abortion, as there was never an embryo. It is important to note that these findings are not diagnostic--a tiny embryo may have existed and then been resorbed--but the findings are also not limited to spontaneous abortion. In the first trimester, declining levels of beta-hCG, echogenic material within an irregularly shaped gestational sac, and heavy bleeding with the passage of clots and tissue all suggest spontaneous abortion.
In the image in question 51, what structure is labeled 3? A.Right ventricle B. Left ventricle C. Right atrium D. Left atrium E. Aorta
D. Left atrium.
What is being measured in this 11-week fetus? A. Chorioamniotic separation B. Nuchal fold C. Cervical spine D. Nuchal translucency E. Cervical cord
D. Nuchal translucency. Explanation: Measurement of the nuchal translucency should be limited to the translucent area only, in the sagittal plane of section, with the digital calipers placed on the inner boundaries at the translucency's widest dimension.
The normal fetal heart occupies: A. One-fourth of the chest cavity and points toward the right side of the fetus B. One-fourth of the fetal chest cavity medially C. One-third of the chest cavity and points toward the right side of the fetus D. One-third of the chest cavity and points toward the left side of the fetus E. One-half of the chest cavity and points toward the left side of the fetus
D. One-third of the chest cavity and points toward the left side of the fetus. Explanation: The fetal heart typically occupies approximately one-third of the chest cavity. The apex of the fetal heart tilts toward the left side of the thoracic cavity. Prenatally the fetal heart is forced by the fetal diaphragm into a position more horizontal than it is postnatally. The diaphragm is situated relatively high in the chest because of the fetus's large liver and uninflated lungs.
Generally, the distance between the fetal orbits should closely approximate: A. Binocular distance B. Interorbital distance C. Interocular distance D. Orbital diameter E. Outer orbital distance
D. Orbital diameter. Explanation: The distance between the orbits--known as the interorbital distance or interocular distance--should generally approximate the diameter of one orbit. A greater than normal IOD suggests hypertelorism, and an IOD that is less than normal indicates hypotelorism. The binocular distance (also called the outer orbital distance) is measured from the lateral edge of one orbit to the lateral edge of the other orbit.
What best describes the anatomy demonstrated by the arrows in this longitudinal image of the fetal spine? A. Dural sac B. Centrum C. Laminae D. Pedicles and laminae E. Transverse process
D. Pedicles and laminae. Explanation: There are 24 articulating vertebrae and 9 fused vertebrae in the sacrum and coccyx, each with three ossification centers. The longitudinal image above demonstrates the pedicles and laminae (arrows) along the fetal spine. By 16 weeks, ossification centers in each vertebra make the spinal column easily visible on sonography.
In the image in question 62, arrow B is pointing to the: A. Right pulmonary artery B. Right atrium C. Right ventricular outflow tract D. Right ventricle E. Aorta
D. Right ventricle.
Which of the following structures is NOT associated with the embryologic development of the soft and hard palates? A. pharyngeal arches B. Lateral palantine processes C. Secondary palate D. Somites E. Primary palate
D. Somites.
A patient presents with a positive pregnancy test and bright red spotting. By dates she is 8-9 weeks. What does this transverse image demonstrate? A. Second gestational sac B. An anembryonic pregnancy C. Normal amnion D. Subchorionic hemorrhage E. Placental abruption
D. Subchorionic hemorrhage Explanation: A subchorionic hemorrhage is blood within the uterine cavity and outside the gestational sac.
When sonographers use the term gestational age, they mean: A. Weeks or days since conception B. Weeks or days since fertilization C. Weeks or days since implantation D. Weeks or days since the first day of the last menstrual period E. Weeks or days since the last day of the last menstrual period
D. Weeks or days since the first day of the last menstrual period Explanation: Gestational age refers to two different methods of calculating the age of the fetus. Embryologists calculate gestational age from the date of conception; this is called conceptual age. If ovulation occurs on day 14 and fertilization occurs about 24-36 hours after that, then fertilization of the ovum happens 15 or 16 days after the beginning of the last menstrual period. In clinical obstetrics, however, the exact date of ovulation is usually unknown, so gestational age is calculated starting with the first day of the last menstrual period, which patients are better able to identify precisely. This is called menstrual age. Menstrual age is therefore a bit less than two weeks greater than conceptual age. When sonographers use the term "gestational age", they typically are referring to menstrual age.
In the image in question 7, what is the arrow pointing to? A. Amniotic cyst B. Fetal head C. Gestational sac D. Yolk sac E. Umbilical cord
D. Yolk sac. Explanation: In the context of ultrasound, "yolk sac" refers to the secondary yolk sac, since the primary yolk sac is not visualized with ultrasound. The secondary yolk sac is the earliest embryonic structure identified sonographically and is demonstrated as early as 5 weeks in a normal gestation, when the mean sac diameter is 5mm or greater. This secondary yolk sac will grow away from the embryo and eventually will be seen between the amnion and the chorion.
Because of spinal segmentation, crown-rump length measurements begin to lose accuracy after how many gestational weeks? A. 3 B. 5 C. 7 D. 9 E. 11
E. 11 Explanation: The most accurate time to date a pregnancy by crown-rump length is in the first trimester, ideally at 10 weeks. By 11 weeks, spinal segmentation begins and gives the fetus the ability to curl, which may affect the accuracy of the measurement.
A rule of thumb for normal renal growth is approximately: A. 5mm per week of gestation B. 4mm per week of gestation C. 3mm per week of gestation D. 2mm per week of gestation E. 1mm per week of gestation
E. 1mm per week of gestation.
When you have demonstrated the fetal stomach transversely at the level of the portal vein, you are at the appropriate level for the: A. Fetal kidneys B. Three-vessel cord C. Cord insertion D. Thoracic circumference E. Abdominal circumference
E. Abdominal circumference.
In the image in question 51, what structure is labeled 4? A. Right ventricle B. Left ventricle C. Right atrium D. Left atrium E. Aorta
E. Aorta. Explanation: This long-axis schematic and correlative sonogram demonstrate the left ventricular outflow tract of the fetal heart.
In this longitudinal scan of the fetal spine, what does the candy-cane shaped vessel to the left of the spine represent? A. Inferior vena cava B. Descending aorta C. Ascending aorta D. Ductal arch E. Aortic arch
E. Aortic arch. Explanation: The aortic arch is best visualized in long axis and appears to the left of the fetal spine. It resembles a candy cane or walking stick, with a tight narrow curve.
What anatomic structure is NOT demonstrated in this image? A. Descending aorta B. Aortic bifurcation C. Right common iliac artery D. Left common iliac artery E. Ascending aorta
E. Ascending aorta.
What is arrow B pointing to in this image in question 90? A. Fourth ventricle B. Thalami C. Peduncles D. Lateral ventricles E. Cisterna magna
E. Cisterna magna.
When does the trilaminar embryonic disc form? A. During organogenesis B. During implantation C. During transit through the fallopian tube D. During neurulation E. During gastrulation
E. During gastrulation. Explanation: Gastrulation is the process in which the three germ layers are formed: ectoderm, mesoderm, and endoderm. "Trilaminar" implies that the disc is made of these three layers.
A patient presents with a positive pregnancy test, bleeding, and cramping. The sonogram reveals an intrauterine gestational sac containing an echogenic structure but no heartbeat. Measurement of the structure shows it to be 11 mm in length. The most likely diagnosis is: A. Anembryonic pregnancy B. Missed abortion C. Placenta previa D. Partial mole E. Early pregnancy failure
E. Early pregnancy failure. Explanation: The inability to demonstrate a yolk sac when the mean sac diameter is 8mm or greater is consistent with a failed pregnancy.
Which sonographic finding is associated with an abnormal pregnancy? A. Spherical gestational sac within the uterus B. Double sac sign within an intrauterine gestational sac C. Oval gestational sac within the uterus D. Defined double decidual ring around the intrauterine gestational sac E. Embryo with a calcified yolk sac
E. Embryo with a calcified yolk sac. Explanation: Secondary yolk sacs should be round (spherical) or oval and well defined. Those that are flat, irregular in shape, calcified, enlarged, absent, or solid in appearance would indicate an abnormal pregnancy with the possibility of impending abortion.
What is the significance of the measurement in Question 40? A. It is a good indicator of gestational age. B. It is an indicator of possible neural tube defects. C. It is a good indicator of possible placenta abruption. D. It is of no practical clinical significance. E. It is a good indicator of possible chromosomal abnormalities.
E. It is a good indicator of possible chromosomal abnormalities. Explanation: An important finding of screening studies in high-risk pregnancies is that there is a strong correlation between chromosomal defects and both thickened fetal nuchal translucency--thickening of the nuchal soft tissues during the first trimester--and maternal age.
The arrow in this image points to the: A. Spinal cord B. Diaphragm C. Inferior vena cava D. Aorta E. Moderator band
E. Moderator band. Explanation: The four-chamber view of the fetal heart remains the standard all sonographers should include in a routine obstetric study. In this projection the four chambers are nicely outlined and the right ventricle can be identified by the moderator band (arrow) in the lower portion of the ventricle.
All of the following are associated with trophoblastic disease EXCEPT: A. Pregnancy induced hypertension B. Theca lutein cysts C. Hypermesis gravidarium D. Large of gestational age E. Normal fetus
E. Normal fetus. Explanation: Every intact conceptus, intrauterine or ectopic, contains trophoblastic tissue, which secretes HCG. The presence in maternal blood of the beta subunit of this glycoprotein hormone is strong evidence of pregnancy. However, grossly elevated beta-hCG can also signal the presence of excessive proliferation of trophoblastic tissue, which can lead to trophoblastic disease, or molar pregnancy. The most common form is the "complete" hydatidiform mole, which represents trophoblastic neoplasia with no embryo. Typically a complete mole fills the uterine cavity and demonstrates a vesicular pattern as seen above. With a "partial" mole, an abnormal embryo or fetus (arrow) coexists with the mole.
This transverse image through the fetal abdomen demonstrates: A. Hypoplastic kidneys B. Renal agenesis C. Enlarged kidneys D. Hydronephrosis E. Normal kidneys
E. Normal kidneys. Explanation: The fetal kidneys are rounded structures on either side of the spine with a "bull's eye" appearance, the calyces being central and echogenic and the cortex hypoechoic. The normal fetal kidney should occupy one-third of the anteroposterior or transverse diameter of the fetal abdomen.
The primitive hindbrain can be seen as a cystic structure within the embryonic head.What is the name of this structure? A. Prosencephalon B. Mesencephalon C. Encephalocele D. Diencephalon E. Rhombencephalon
E. Rhombencephalon. Explanation: The embryonic brain is a collection of cystic cavities surrounded by thin mantles of neural tissue. In the fetus the rhombencephalon compromises the hindbrain structures. During the first and second trimesters--as seen in this image of an 8 week gestation--the rhombencephalon (arrow) typically appears prominent. However, the appearance of a prominent rhombencephalon after the second trimester suggests a Dandy-Walker formation--cystic dilatation of the fourth ventricle, hypoplasia or complete absence of the vermis, an enlarged posterior fossa, and hydrocephalus.
What is demonstrated by arrow A in this short-axis view of the fetal heart? A. Right ventricle B. Right ventricular outflow tract C. Right pulmonary artery D. Aorta E. Right atrium
E. Right atrium.
In this image the arrow labeled A points to the: A. Ventricular septum B. Right atrium C. Left ventricle D. Left atrium E. Right ventricle
E. Right ventricle.
This patient is at 10 weeks, but her doctor feels that she is small for gestational age and he cannot hear any fetal heart tones. He orders a sonogram to confirm viability. An M-mode was not included. Referring to this image, what do you expect? A. There are two sacs of about 5 weeks in size, suggesting twins. B. She is not really pregnant, suggesting pseudocyesis. C. She has an ectopic pregnancy. D. The sac is too large for the embryo/fetus inside, suggesting an abnormal pregnancy. E. The sac is too small for a 10-week gestation, suggesting incorrect dates.
E. The sac is too small for a 10-week gestation, suggesting incorrect dates. Explanation: By 8 weeks, the normal gestational sac should occupy one-half of the uterine cavity and show a yolk sac, embryo, and heartbeat. By 10 weeks, the sac should have grown to fill the uterine cavity, and a well-defined fetus should be apparent.
Below is a transvaginal sagittal image of a 9-week intrauterine pregnancy. What is the finding? A. Incomplete abortion B. Calcified yolk sac C. Spontaneous abortion D. Inevitable abortion E. Threatened abortion
E. Threatened abortion. Explanation: This image reveals a gestational sac with a subchorionic hemorrhage. A patient who presents with vaginal bleeding at less than 20 weeks is said to have a threatened abortion.
Thoracic circumference is measured in the: A. True longitudinal view at the level of fetal four-chamber heart B. Longitudinal view at the level of the diaphragm and just below fetal four-chamber heart C. True transverse view just below the fetal diaphragm and at the level of fetal heart motion D. True transverse view just below the fetal diaphragm and just above fetal four-chamber heart E. True transverse view at the level of fetal four-chamber heart
E. True transverse view at the level of fetal four-chamber heart
In this image of a first trimester pregnancy the arrow is pointing to: A. Ductus venosus B. Synechiae C. Amniotic band D. Umbilical cord E. Vitelline duct
E. Vitelline duct. Explanation: The vitelline duct (also called the omphalomesenteric duct) is the structure that initially maintains a connection between the yolk sac and the embryo once they diverge from each other. The vitelline duct contains an artery and vein through which nutrients and blood elements are transported from the yolk sac to the embryo.
What is the arrow pointing to in this image? A. Cystic mass B. Amnion C. Embryo D. Ovum E. Yolk sac
E. Yolk sac Explanation: This sonogram demonstrates a gestational sac with a yolk sac (arrow) situated normally between the amnion and chorion. This is the secondary yolk sac, which forms after regression of the primary yolk sac. The primary yolk sac cannot be appreciated on sonography; the secondary yolk sac is the earliest embryonic structure identified by ultrasound and can be visualized by 5-6 menstrual weeks, when the mean sac diameter is 5mm or greater.
