Based on an original presentation by Hing Har Lo, MD Chair, Radiology/Nuclear Medicine Dr. Januchowski 2012

 Name the different Imaging modalities available for the OB/GYN patient  Compare and contrast the modalities available  Know the different indications for imaging of the OB/GYN patient  Choose the most appropriate modality based on the clinical presentation and desired results  Recognize common OB/GYN Clinical presentations on imaging

 X-Ray ‏  Ultrasound (US) ‏  Most important imaging  Computerized Tomography (CT) ‏  Magnetic Resonance Imaging (MRI) ‏

 a low-dose, low voltage x-ray exam of the  The results are recorded on x-ray film or directly into a computer (digital)  Lump or mass  Calcifications: Macrocalcifications are large calcium deposits often caused by aging. These usually are not a sign of cancer. Microcalcifications are tiny specks of calcium that may be found in an area of rapidly dividing cells.  Distortion  Still the diagnostic tool for detecting breast cancer  Recommend screening after 40 yo

MLO of a fatty breast Small carcinoma Dense breast CC (cranial caudate) Analog Digital

Performed with observing with fluoroscopy Injecting iodinated contrast via the catheter in the cervix/uterus/fallopian tubes Infertility evaluation Repeated miscarriages Monitor tubal patency after surgery A: right tube, B: uterine cavity, C: left tube, D: catheter with balloon tip Spillage into pelvis

Need a full bladder for an acoustic window. Sagittal scan through the long axis of uterus

Need a empty bladder. Adapted from: Danforth's Obstetrics and Gynecology 9 th Edition A transducer in vaginal probe inserted.

 Sending high frequency sound waves in the transducer,  Produce “echoes” of varying intensities received by the transducer ) ‏ Hyperechoic (echogenic) ‏ Isoechoic Isoechoic Hypoechoic Anechoic Echoes

Acoustic shadowing Acoustic enhancement Acoustic enhancement Calcification

Uses x-ray beams & detector arrays Attenuation, density Barium in small bowel uterus air in colon

Strong magnetic field Radio frequency (RF) ‏ Signal

 Which of the following modalities would expose the patient to the largest amount of radiation? Ultrasound of the pelvis MRI of the abdomen Hysterosalpingogram Abdominal flat plate Mammography  SEE NOTES FOR ANSWER

 Obstetrics  Growth & development  Fetal well-being  Abnormal  Gynecology  Anomalies  Inflammatory  Neoplastic  Other

Gestational sac visible ~ 4 weeks Yolk sac visible ~ 4 -5 weeks Embryo visible ~ weeks Heartbeat ~ weeks Preembryonic period (conception to 5 menstrual wks); Embryonic period, during which time organogenesis is the major activity (4 to 9 menstrual weeks); Early developmental or fetal period, during which time the fetus continues to grow.

 A gestational sac appears as a double ring that is comprised of the decidua capsularis and the decidua parietalis.  The sac should be seen when the β human chorionic gonadotropin (hCG) is between 1,000 and 2,000 mIU/mL.  Once identified, the sac diameter should grow by an average of 1 mm per day Yolk sac

Crown-rump length

Biparietal diameter (BPD) Head circumference (HC) Abdominal circumference (AC) Femur length (FL)

Gestational age Fetal weight Fetal growth

CRL: +/- 3-4 days BPD, HC, AC, FL wks GA: +/- 1 wk wks GA: +/- 2 wks > 30 wks GA: +/- 3 wks

 Use US age < 22 weeks  Use menstrual age > 22 weeks  Do not alter GA by US after 22 weeks  Unless late 1 st prenatal evaluation  Unsure of LMP

 There are more than 40 formulas in the literature for estimated fetal weight (EFW).  The Hadlock formula, which is incorporated into most North American ultrasound machine software packages, utilizes four variables: the BPD, HC, AC, and FL.  Not highly accurate, but..  Benefits  Growth rate evaluation  Preterm labor

454gm=1lb Amniotic Fluid Index

Evaluate for fetal distress (hypoxia) Use Fetal Biophysical Profile

1. Heart rate reactivity (non-stress test) 2 or more episodes of acceleration of ≥ 15 bmp and of >15 s associated with fetal movement within 20 min 2. Sufficient amniotic fluid: 1 or more pockets of fluid measuring ≥ 2 cm in vertical axis 3. Fetal tone :1 or more episodes of active extension with return to flexion of fetal limb(s) or trunk (opening and closing of hand considered normal tone) 4. Fetal movement 5. Fetal breathing Attempt to identify fetal distress (hypoxia) Analogous to neonatal Apgar score Points for each: 2 or 0 Normal: 8 – 10 points Suspicious: 6 points Abnormal: < 6 points

Tone 2 pts Breathing 2 pts Movement 2 pts Amniotic fluid 2 pts

Identify intrauterine pregnancy: Gestational sac Yolk sac Embryo Middleton: Ultrasound - The Requisites, 2nd ed Mosby Embryonic heart rate: Should not be less than bpm. Normally bpm after 8 weeks Bradycardia often associated with miscarriage Less than 90 bpm at 5-6 weeks Less than 120 bpm after 8 weeks By 6 weeks: Should see heart beat by transvaginal US. If no embryo, or embryo without heartbeat – likelihood of miscarriage. By 7+ weeks: Normal heart beat implies high likelihood of progression to term.

 Under ideal situations, at what gestational age would the gestational sac be visible on transvaginal pelvic ultrasound? 4 weeks 5 weeks 6 weeks 7 weeks  ANSWER ANSWER

 At what range would crown-rump length be the best measurement for the estimation of fetal gestational age? 0-5 weeks 6-14 weeks weeks weeks  ANSWER ANSWER

 Which of the following factors would be a part of the biophysical profile ultrasound to assess fetal well being? Umbilical artery flow rate Femur length Abdominal circumference Fetal heart rate Fetal lie  ANSWER ANSWER

Relative risk of preterm delivery increases as cervical length decreases. Normal > 25mm. 25 mm optimal cutoff for predicting preterm delivery at all gestational ages. 40mm

Usually due to placental insufficiency Increased risk for fetal distress

Usually due to placental insufficiency Placenta requires adequate blood flow From Danforth's Obstetrics and Gynecology 9 th Edition Normal Uterine Artery WaveformAbnormal Uterine Artery Waveform Doppler Ultrasound

Doppler US ROI is at cardiac position of the fetus

Hydrocephalus Encephalocele Anencephaly Adapted from Gabbe: Obstetrics: Normal and Problem Pregnancies, 5th ed. 2007

Danforth's Obstetrics and Gynecology 9 th Edition

Adapted from: Danforth's Obstetrics and Gynecology 9 th Edition

Adapted from: Gestational trophoblastic disease Placental neopastic process Usually benign

 Find IUP by transvaginal US  Note: Heterotopic pregnancy 1 in 4000 –  Discriminatory β hCG level  Point at which all IUPs should be visible on TVUS  Third International Standard: ~ mIU/mL  Exception: multiple gestations  US visualization of extrauterine gestational sac

Free fluid Uterus Free Fluid Ectopic GS Adapted from Gabbe: Obstetrics: Normal and Problem Pregnancies, 5th ed. 2007

 Which of the following ultrasound findings would indicate that a patient may be at higher risk for preterm labor? Fetal weight at <5 th percentile Uterine wall hypertrophy Cervical length < 25 mm Marginal placental previa  SEE NOTES FOR ANSWER

Clinical presentations Obstetrics Growth & development Fetal well-being Abnormal Ectopic Gynecology Uterine Anomalies Inflammatory Neoplastic Miscellaneous

radiology.rsnajnls.org Infertility Miscarriage Ectopic pregnancy

imaging.consult.com Danforth's Obstetrics and Gynecology 9 th Edition Transverse US: Bicornuate or septated uterus Coronal MRI: Bicornuate Uterus

Berek & Novak's Gynecology Left adnexa: Tubo-ovarian abscess

Benign Leiomyomata (fibroids) Ovarian teratoma (dermoid) Malignant Uterine Ovarian

Berek & Novak's Gynecology Ultrasound MRI NOTE: Most fibroids will be seen with smooth edges on ultrasound

Ultrasound CT Tooth

Normal endometrial thickness < 5mm post-menopausal

Functional (physiologic) Follicular Corpus luteum cyst Often acute abdominal pain due to: Large size Torsion Rupture Hemorrhage

Follicular Cyst Corpus Luteum Cyst Hemorrhagic Cyst

Normal right ovary Torsion left ovary Post-op left ovary

Normal ovary PCOS “String-of-pearls” sign

Pelvic congestion is becoming increasingly recognised as a cause of chronic pelvic pain. It is associated with pelvic varicosities, increased blood flow

 An ultrasound is done on a postmenopausal female for evaluation of vaginal bleeding. Which of the following findings would be most indicative of endometrial cancer in this patient? String of pearls sign Endometrial thickness of 7 mm Mass with smooth edges noted on ultrasound Increased blood flow to the pelvis  ANSWER ANSWER

The End !