ULTRASOUND OF FETAL OVARIAN CYSTS
  • Female fetus.
  • Cyst size variable (2-8cm).
    1. Above and distinct from urinary bladder.
    2. Below and distinct from fetal stomach and gallbladder.
    3. Exclude abnormalities of the spine, GI tract and urinary system.
  • 85-90% are cystic (follicular or luteinic origins).
  • 10-15% are organic (< 3% are carcinomas and 7-12% are teratomas, mucinous or serous cystadenomas).

      Ovarian carcinoma has been rarely reported:

·         Ziegler et.al. (1945) (1) – bilateral ovarian carcinoma in a 30 week fetus.

·         Henrion et.al. (1987) (2) – ovarian malignancy represents 3.5% of neonatal ovarian masses.

 

 

 

CLASSIFICATION / ULTRASOUND

Six classes are described according to sonographic and pathologic appearance of the cyst (1-9).

    1. Simple and anechoic with an imperceptible wall.
    2. May have a fluid - debris level.
    3. Cyst with a retracting clot.
    4. Cyst with septations (considered simple if no internal echoes are present).
    5. Solid appearing.
    6. “Daughter cyst” – cyst within or outside the main cyst (3,9).

·         Lee et.al. (3) Sensitivity 82%, specificity 100% confirming ovarian origin.

·         Thought to be due to hormonal dysfunction leading to genesis of follicular and lutenic cysts. Corresponds to an excessively developing intra-ovarian follicle just before ovulation.

·         Appearance identical to a Graffian follicle with cumulus oophorus.

Groups 2 to 5 are considered complicated.

 

Simple ovarian cyst

Ovarian torsion

 

 

 

 

Ovarian cyst with retracting clot

 

 

 

 

Complex ovarian cyst with septation

Ovarian torsion

 

 

Cystic mass

Hemorrhage within

Separate from kidney and stomach

 

 

 

Retracting clot within

 

Avascular on power doppler

 

 

 

Female fetus

Bilateral multiseptated ovarian cysts

C – cyst

B - bladder

 

SONOGRAPHIC SIGNS OF TORSION (6-8)
    1. Torsion ocured prenatally in 38% of cases in Brandt’s series (10).
    2. Septae developing within simple cyst (representing strands of necrotic cells that have separated from the wall of the cyst due to ischemia).
    3. Irregular echogenic material within the cyst due to intracystic hemorrhage.
    4. Fluid debris level develops as the hematoma liquefies.
    5. A retracting clot forms at the bottom of the cyst due to organization of the hematoma.
    6. Ascites if rupture occurs.

 

 

REFERENCES
  1. Ziegler EE. Bilateral ovarian carcinoma in a thirty week fetus. Arch Pathol 1945:40:433-434.
  2. HenrionR, Helardot PG. In utero disgnosis of cysts of the ovary (in French). Ann Pediatr (Paris) 1987;34:65-69.
  3. Lee H-J, Woo S-K, Kin J-S et.al. Daughter cyst sign: a sonographic sign of ovarian cyst in neonate, infants and young children. Am J Roentgenol 2000;174:1013-1015.
  4. Nussbaum AR, Sanders RC, Hartman DS et.al. Neonatal ovarian cysts: sonographic-pathologic correlation. Radiology 1988;168:817.
  5. Garel L, Filiatrault D, Brandt M et.al. Antenatal diagnosis of ovarian cysts: natural history and therapeutic implications. Pediatr Radiol 1991;21:182-184.
  6. Shozu M, Akasofu K, Yamashiro G et.al. Changing ultrasonographic appearance of a fetal ovarian cyst twisted in utero. J Ultrasound Med 1993;12:415-417.
  7. Widdowson DJ, Pilling DW, Cook RC. Neonatal ovarian cysts: therapeutic dilemma. Arch Dis CHILD 1988;63:737.
  8. Gaudin J, Treguilly CL, Parent P et.al. Neonatal ovarian cysts. Twelve cysts with antenatal diagnosis. Pediatr Surg Int 1988;3:158.
  9. Quarello E, Gorinicourt G, Merrot T et.al. The “daughter cyst” sign: a sonographic clue to the diagnosis of fetal ovarian cyst. Ultrasound Obstet Gynecol 2003;22:431-436.
  10. Brandt ML, Luks FI, Filatrault D et.al. Surgical indications in antenatally diagnosed ovarian cysts. J Pediatr Surg 1991;26:276-282.