3397

Mirror image artifact of normal uterus mimicking double uterusKim T-S, Park O-R, Yi M-G, Mirae Woman’s Hospital, Korea;Daegu Fatima Hospital, Korea

Mirror image artifact during ultrasound is a double reflection at certaintissue plane like diaphragm or muscles. A 31-year old woman, gravida1 para 0, came to our hospital for routine antenatal care. Routinetransvaginal sonographic scanning at early pregnancy was unremark-able with normal shaped uterus with IUP and two ovaries. At term shedelivered a 3120 gm female and was discharged uneventfully. Threemonths later she returned to our hospital for routine check up. Attransvaginal sonography there was a didelphys like double uterus,which was different from previous sonographic finding. And we re-examined the uterus with high resolution sonography, and it wasnormal appearance. We think that the reflection plane was rectal airposterior to the uterus and the plane acted as mirror to ultrasound beam.If there is any doubt of this artifact, change the frequency or mode ofultrasound probe.

3398

Changes in the gestational and yolk sac volumes with normalpregnancy and missed abortion by three-dimensionalultrasonographyKim MJ, Kim EJ, Hur SY, Lee GS, Kim SJ, Holy Family Hospital ofCatholic University, Korea

Objectives: The volume of embryonic structures including gestationalsac volume (GSV), yolk sac volume (YSV) and yolk sac diameter(YSD) may have prognostic value during the first trimester. The aim ofthis study was to investigate whether first-trimester volume calculationsof these structures using transvaginal three-dimensional ultrasoundtechnique may have value as first trimester pregnancy.Methods: Between January 2004 and October 2005, 408 patients withsingleton pregnancies were included in the first trimester. A singleinvestigator performed all sonographic examinations and measure-ments. GSV and YSV were calculated by VOCAL (virtual organcomputer aided analysis) technology using a 7-MHz transvaginal trans-ducer (Accuvix XQ, Medison, Seoul, Korea).Results: There is comparison of threatened abortion and missed abor-tion’s YSV, GSV ratio, which shows meaningful gap from missedabortion. As a result, It shows YSV, YSV and GSV’s ratio meaningfulgap from missed abortion.Conclusions: These results suggest that three-dimensional ultrasonog-raphy can become an important modality in future embryological andearly fetal research and detection of embryonic and fetal developmentin the first trimester of pregnancy.

3399

A case of massive subchorionic thrombohematoma: Diagnosedby ultrasonography and magnetic resonance imaging inmidpregnancyKim SJ, Kim MJ, Hur SY, Lee HJ, Lim HW, Lee GS, Shin JC, HolyFamily Hospital of The Catholic University, Korea; Dept. ofPathology, Korea; Dept of Radiology, Korea; Vincent Hospital ofthe Catholic Hospital, Korea; St Mary’s Hospital of the CatholicUniversity, Korea

Placental abnormality is the important predisposing cause of intrauter-ine growth retardation. Massive subchorionic thrombohematoma isdefined as a large size of maternal blood clot that separates the chori-onic plate from the villous chorion and can result in serious obstetricalcomplications. Placental enlargement was detected in a 36-year old

primipara woman with fetal growth retardation and oligohydramnios isat 17 weeks gestation. 2D and 3D ultrasonography showed an abnormalsonolucency within the placenta, but could not give an unequivocaldifferentiation from placental abnormalities such as hematomas, cystsand other tumors. Therefore it might be difficult to make a discrimi-nation of massive subchorionic thrombohematoma by USG only, andmagnetic resonance imaging (MRI) may be useful for discrimination ofplacental abnormalities. We report a case of massive subchorionicthrombohematoma diagnosed prenatally, and propose an additionalequivocal finding confirmed by ultrasonography and magnetic reso-nance imaging (MRI).

3400

Broad spectrum of ultrasound findings of hydatidiform mole andmolar mimickerJung SI, Cho JY, Moon MH, Lee YH, Song MJ, Kim J-A, Min JY,Kim MY, Samsung Cheil Hospital, Sungkyunkwan University Schoolof Medicine, Korea

US play an important role in determining the presence of hydatidiformmole. The US finding of hydatidiform mole is solid collection of echoeswith numerous anechoic spaces, so called “snowstorm” appearance.These findings suggest edematous chorionic villi with trophoblasticproliferation. But incomplete abortion as hydropic abortus may haveedematous chorionic villi with trophoblastic proliferation though thevilli in nonmolar abortions have less pronounced edema. Subchorionichematoma is very common in early pregnancy may show various kindsof US findings from huge solid mass to multilocular cyst. Hematomaoccurred shortly after dilatation and curettage of uterus for abortionmay mimic pathologic condition as hydatidiform mole or invasivemole. We illustrate the various kinds of US findings of hydatidiformmole and molar mimicker as incomplete abortion, subchorionic hema-toma and hematoma after dilatation and curettage of the uterus.

3401

Fetal heart rate independent parameter of cardiac contractility:Fetal isovolumetric contraction time in a case with fetaltachyarrhythmiaFujita Y, Trudinger B, University of Sydney at Westmead Hospital,Australia

The isovolumetric contraction time (ICT), an index of cardiac contrac-tility, is the time interval between the onset of the ventricular contrac-tility and cardiac ejection. We have described a simple Doppler systemto measure this. In this case report, we measured the ICT sequentiallyin a fetus with a tachyarrhythmia diagnosed at 37 week gestation andwe sought to examine whether this parameter is independent of fetalheart rate. Despite of fetal tachycardia of over 200 bpm, the fetal ICTshowed a normal value. After cardioversion using maternal digoxin, thefetal heart rate returned to normal. Sequential measurements of the fetalICT showed a gradual lengthening of the ICT associated with fetalgrowth failure and operative delivery for fetal distress. After birth, thearrhythmia disappeared without any medication. This case highlightsthe fact that the fetal ICT is independent of fetal heart rate and its usein prediction of deteriorated fetal condition.

3402

Effects of maternal positions on the umbilical arterial DopplerwaveformsKim YH, Song T-B, Kim CH, Cho MK, Kim KM, Chonnam NationalUniversity Medical School, Dept. of Ob/Gyn, Korea

P258 Ultrasound in Medicine and Biology Volume 32, Number 5S, 2006