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M C Frates

Publications and source records attributed to M C Frates.

At least 19 recordsLinked to original sources
PubMed1999

Sonographic spectrum of the corpus luteum in early pregnancy: gray-scale, color, and pulsed Doppler appearance.

PURPOSE: We describe the gray-scale and Doppler sonographic features of the corpus luteum during the first trimester of pregnancy. METHODS: Using transvaginal sonography, we prospectively evaluated the ovaries of 160 patients with spontaneous singleton intrauterine gestations between 5 and 8 weeks' menstrual age. Size, sonographic appearance, resistance index, and peak systolic velocity were recorded. RESULTS: The corpus luteum was identified in 157 (98%) of 160 patients. The mean diameter was 1.9 +/- 0.6 cm. The most common appearance was a round hypoechoic structure, found in 54 patients (34%). Other appearances included a cyst with a thick wall and anechoic center (43 patients, 27%), a cyst containing internal debris (36 patients, 23%), and a thin-walled simple cyst (24 patients, 15%). Corpus luteal blood flow was visualized with color Doppler imaging in 92% (145/157) of patients in whom the corpus luteum was found. Color Doppler imaging typically revealed a circumferential rim surrounding part or all of the corpus luteum. Low-resistance blood flow was seen with pulsed Doppler interrogation, with a mean resistance index of 0.49 +/- 0.08 and mean peak systolic velocity of 17 +/- 10 cm/second. CONCLUSIONS: The corpus luteum in early pregnancy is routinely identified with transvaginal sonography and has a wide range of sonographic appearances. Recognizing the various appearances of the corpus luteum is important to avoid confusing them with true ovarian abnormalities.

Adult↗
PubMed1998

Benign and malignant ovarian masses: selection of the most discriminating gray-scale and Doppler sonographic features.

PURPOSE: To determine the gray-scale and Doppler sonographic features that best enable discrimination between malignant and benign ovarian masses and develop a scoring system for accurate diagnosis with these features. MATERIALS AND METHODS: Gray-scale and Doppler sonographic features of 211 adnexal masses were correlated with the final diagnosis; the most discriminating features for malignancy were selected with stepwise logistic regression. RESULTS: Twenty-eight masses were malignant and 183 benign. All masses with a markedly hyperechoic solid component or no solid component were benign. For masses with a nonhyperechoic solid component, additional features that allowed statistically significant discrimination of benignity from malignancy were, in decreasing order of importance, (a) location of flow at conventional color Doppler imaging, (b) amount of free intraperitoneal fluid, and (c) presence and thickness of septations. A scoring formula that made use of values based on the logistic regression equation had an area under the receiver operating characteristic curve of 0.98 +/- 0.01. The cutoff score with the highest accuracy had a sensitivity of 93% and specificity of 93%. CONCLUSION: A solid component is the most statistically significant predictor of a malignant ovarian mass. A multiparameter scoring system that uses three gray-scale and one Doppler feature, developed by means of stepwise logistic regression, has high sensitivity and specificity for predicting malignancy.

Adolescent↗
PubMed1998

Sonographic evaluation of the placental cord insertion site.

OBJECTIVE: Velamentous and marginal umbilical cords are uncommon abnormalities of placental cord insertion that can entail significant fetal risk. We undertook this investigation to assess the ability of prenatal sonography to reveal abnormal insertions of the umbilical cord into the placenta. SUBJECTS AND METHODS: Forty-six patients had both prenatal sonographic evaluation of the placental cord insertion site and postnatal pathologic examination. Distance from the insertion site to the nearest placental edge was categorized by sonography and pathology as normal if greater than 1 cm and abnormal if less than or equal to 1 cm. Sonographic and pathologic findings were compared. RESULTS: Thirty-eight singleton and eight twin pregnancies, for a total of 54 cord insertions, were studied. Of the 43 sonographically normal insertions, 38 had normal pathologic findings, and the remaining five insertions had abnormal pathologic findings (all marginal cord insertions). All 11 insertions that showed abnormality on sonography were abnormal on pathologic examination (seven marginal and four velamentous insertions). Sonography was able to reveal a difference between the two types of abnormal insertions in only a single patient, in whom the cord insertion changed from marginal to velamentous during a 7-week interval. Sonography had an overall sensitivity of 69% (11/16), a specificity of 100% (38/38), and an accuracy of 91% (49/54) for revealing abnormal placental cord insertion sites. CONCLUSION: Targeted sonographic examination of the placental site of umbilical cord insertion will reveal abnormal placental cord insertions, although distinguishing the specific type of abnormal insertion may require the use of color Doppler imaging.

Chorion↗
PubMed1997

Early singleton pregnancy outcome: effects of maternal age and mode of conception.

PURPOSE: To assess the effect of prognostic factors on the outcome of singleton pregnancies. MATERIALS AND METHODS: First-trimester ultrasonographic (US) scans that demonstrated a living fetus in 4,156 consecutive singleton pregnancies were studied. The relationship between outcome and maternal age, mode of conception, maternal symptoms, and US findings was evaluated. RESULTS: Spontaneous abortion occurred in 371 of 4,156 (8.9%) cases. Higher pregnancy-loss rates were associated with older maternal age (P < 10(-5)), assisted mode of conception (P < 10(-8)), maternal symptoms of pain and/or bleeding (P < .001), and abnormal US findings (P < 10(-8)). US abnormalities were more frequent in older women than in younger women (P < 10(-5)) and in assisted conceptions than in natural conceptions (P < 10(-8)). At stepwise logistic regression, with gestational age as a covariate, US abnormalities and maternal symptoms independently affected pregnancy outcome. Maternal age and mode of conception had no further statistically significant effect on pregnancy outcome. CONCLUSION: The prognosis for older mothers and for those with assisted conception is not statistically significantly different from that for younger mothers and for those with natural conception if maternal symptoms, US findings, and gestational age are the same.

Abortion, Spontaneous↗
PubMed1997

Solid extratesticular masses evaluated with sonography: pathologic correlation.

PURPOSE: To determine if the sonographic appearance of solid extratesticular masses enables distinction of benign from malignant disease. MATERIALS AND METHODS: Sonograms of 19 patients with palpable testicular masses who underwent biopsy were reviewed retrospectively. Appearances of masses on sonograms were correlated with pathologic diagnoses. RESULTS: All masses were well defined and ranged in size from 5.7 to 66.7 mm (mean, 21 mm). On the sonograms, five masses were within the epididymis, and six were distinct from it; seven cases were indeterminate. The epididymis was surgically absent in the remaining patient. Sonographic echogenicity ranged from hypoechoic to hyperechoic relative to that of the testis. At pathologic evaluation, there were 16 (84%) benign and three (16%) malignant lesions. Benign lesions consisted of six adenomatoid tumors, two lipomas, two epidermoid inclusion cysts, two cases of sarcoidosis, and one case each of sperm granuloma, spermatic cord leiomyoma, benign inflammatory nodule, and fibroma. The malignant lesions consisted of scrotal wall liposarcoma, epididymal leiomyosarcoma, and recurrent spindle cell malignancy of the spermatic cord. No sonographic features of masses were useful for distinguishing benign from malignant lesions. CONCLUSION: The frequency of malignancy (16%) contrasts with prior reports that suggest a very low rate of malignancy among these masses. Sonography is useful for identifying the extratesticular location of a mass but not for distinguishing the nature of the lesion.

Adult↗
PubMed1997

Clinical significance of isolated enlargement of the cisterna magna (> 10 mm) on prenatal sonography.

Enlargement of the cisterna magna has been reported to be associated with aneuploidy. In prior studies of cisterna magna enlargement, however, those fetuses with abnormal chromosomes have had other sonographic abnormalities in addition to a large cisterna magna. Our goal was to assess the clinical significance of the isolated finding of a cisterna magna measuring more than 10 mm in anteroposterior dimension on a prenatal sonogram. We retrieved all prenatal sonograms performed at our institution between 1989 and 1996 in which an enlarged cisterna magna was the only sonographic abnormality. Cases were included in our study if the cisterna magna measured more than 10 mm in the appropriate plane and the fetal survey was otherwise normal, including normal cerebellar size and morphology. Pregnancy outcome and postnatal follow-up were obtained in each case. Fifteen cases comprised our study population. In all 15 fetuses, the enlarged cisterna magna was first seen in the third trimester (gestational age range, 26 to 37 weeks). The cisterna magna ranged from 11 to 19 mm in size (mean, 12.9 mm). All 15 pregnancies resulted in phenotypically normal liveborn infants. All the mother and infants had short hospital stays (1 to 4 days), and the infants were normal at discharge. Longer follow-up was available in eight cases (range, 2 to 69 months), and all eight of these infants were normal. Our results suggest that isolated enlargement of the cisterna magna to more than 10 mm is associated with normal pregnancy and neonatal outcome.

Cisterna Magna↗
PubMed1997

Hemobilia: sonographic appearances in the gallbladder and biliary tree with emphasis on intracholecystic blood.

The purpose [corrected] of this study is to discuss the causes and sonographic appearances of blood in the gallbladder and biliary tree. Over a 12 year period, 18 patients with hemobilia had ultrasonographic examinations at one of three hospitals. Hemobilia was categorized as traumatic (50%), spontaneous (28%), or inflammatory (22%), with coagulopathy present in half of the cases. The sonographic appearances of intracholecystic blood varied, but with the exception of a single case, masslike intracholecystic material was present. Biliary dilatation occurred in five patients, with echogenic material visible in the extrahepatic bile duct in three of these cases.

Adult↗
PubMed1996

Role of Doppler ultrasonography in the prediction of pregnancy outcome in women with recurrent spontaneous abortion.

We prospectively studied 96 patients with a history of recurrent spontaneous abortion to determine whether the resistive index of the main uterine artery or subchorionic vessels can allow prediction of pregnancy outcome. The subchorionic RI declined progressively for a mean of 0.54 at 6 weeks to 0.42 at 13 weeks (P < 10(-8), F-test). No significant difference was found in subchorionic RI values between outcomes for liveborn infants versus loss. Uterine artery RI values also declined significantly through the first trimester (P < 10(-8), F-test). Uterine artery RI values tended to be lower in pregnancies ending in loss than in successful gestations; however, there was too much overlap for this index to be clinically useful. In conclusion, first trimester RI does not allow prediction of pregnancy outcome in patients with recurrent abortion.

Abortion, Habitual↗
PubMed1995

Increasing curvature of the normal fetal ductus arteriosus with advancing gestational age.

In order to determine whether the configuration of the normal fetal ductus arteriosus changes with increasing gestational age, we prospectively collected oblique transverse sonographic images of the fetal thorax through the ductus arteriosus. Scans from 240 consecutive normal fetuses with gestational age 20 weeks or more were included in the study. The images were reviewed independently by two sonologists and the ductus arteriosus was graded as: (1) straight; (2) mildly curved (C-shaped, bending < 90 degrees from a straight line); or (3) markedly curved (C-shaped, bending > 90 degrees, or S-shaped). In cases where the two sonologists' gradings did not concur, the images were re-reviewed jointly by both sonologists and a grading was assigned by consensus. Forty-two cases were rejected, due to inadequate images. The ductus arteriosus was graded in 42 fetuses aged 20-25.9 weeks, 48 at 26-31.9 weeks, 74 at 32-37.9 weeks, and 34 at 38 weeks or more for a total of 198 cases. There was a significant trend to greater curvature with increasing gestational age (p < 0.0001). The frequency of a straight ductus arteriosus decreased steadily from 55% of fetuses aged 20-25.9 weeks to 3% of fetuses at 38 weeks or older, while the frequency of marked curvature increased from 2% in the youngest age group to 56% in the oldest. The proportion with mild curvature showed little variation throughout gestation. In summary, the configuration of the ductus arteriosus is variable but tends to become more curved as pregnancy proceeds. Marked curvature or tortuosity of the ductus arteriosus should not be misinterpreted as a great vessel anomaly.

Ductus Arteriosus↗
PubMed1995

Sonographic evaluation of ectopic pregnancy: an update.

This review addresses the use of state-of-the-art sonography to evaluate patients with possible ectopic pregnancy (EP). The technical aspects for optimizing the examination are emphasized, and the role of color and pulsed Doppler imaging is discussed. The various sonographic criteria used to diagnose EP are critically analyzed. In addition, imaging findings for some of the more unusual forms of EP are discussed. The role of sonography in the treatment of EP is briefly considered.

Adnexa Uteri↗
PubMed1994

Early diagnosis and treatment of cervical pregnancy in an in vitro fertilization program.

This is a report of three cervical pregnancies, one of which was a heterotopic twin cervical pregnancy that occurred in combination with a single intrauterine pregnancy. Transvaginal ultrasound examination was sufficient to establish the diagnosis in two of three patients, and MRI scanning was conclusive in the third. Early diagnosis lead to intervention before 7 weeks gestation in all cases with no complications. The incidence of cervical pregnancy may be higher in IVF-ET than recognized previously.

Adult↗
PubMed1994

Ovarian masses: can benign and malignant lesions be differentiated with color and pulsed Doppler US?

PURPOSE: To determine whether color and pulsed Doppler ultrasound (US) can be used to differentiate benign from malignant ovarian masses. MATERIALS AND METHODS: Forty-four ovarian masses identified with sonography in 40 patients were confirmed at surgery (n = 35) or followed up to resolution with US (n = 9). Color and pulsed Doppler US were used to calculate the lowest pulsatility index (PI) and resistance index (RI) for each mass. RESULTS: Color Doppler US enabled detection of arterial flow in 24 of 36 benign masses and six of eight malignant masses. PI was lower in malignant masses than in benign masses (P = .002), as was RI (P = .001). Both indexes demonstrated overlap between benign and malignant masses; therefore, no cutoff value for either index had both high sensitivity and high specificity for malignancy: For PI cutoff of 1.0, sensitivity and specificity were 100% and 46%, respectively; for RI cutoff of 0.4, 50% and 96%. CONCLUSIONS: While PI and RI tend to be lower in malignant ovarian masses, neither index can be used reliably to differentiate benign from malignant lesions. In addition, lack of detectable flow by means of color Doppler US does not exclude ovarian malignancy.

Adult↗
PubMed1994

Tubal rupture in patients with ectopic pregnancy: diagnosis with transvaginal US.

PURPOSE: To determine whether sonography can help diagnose tubal rupture in patients with ectopic pregnancy. MATERIALS AND METHODS: The authors reviewed the transvaginal ultrasound (US) scans and medical records of 132 consecutive patients with tubal pregnancy confirmed at surgery performed within 24 hours of undergoing US. RESULTS: Adnexal masses were seen in 93 patients at US. Thirty-four patients had a tubal ring, and 59 had a complex mass. The frequency of tubal rupture was similar for both groups. The adnexal mass was significantly smaller in patients without a ruptured tube, but there was considerable overlap. Rupture was present in 21% of patients with no sign of or a trace of intraperitoneal fluid, increasing steadily to 63% in patients with a large amount of free fluid. Even though the amount of fluid was the best predictor of rupture, it was not completely reliable, as 37% of patients in whom a large amount of fluid was found had intact tubes. CONCLUSION: No finding at transvaginal US is a reliable indicator of rupture. Contrary to findings from previous studies, the appearance of the adnexal mass, if present, is not related to tubal rupture.

Fallopian Tube Diseases↗
PubMed1994

Cervical ectopic pregnancy: results of conservative treatment.

PURPOSE: To review experience with early sonographic diagnosis and fertility-preserving treatment of cervical ectopic pregnancy. MATERIALS AND METHODS: The authors evaluated 12 consecutive cases of cervical ectopic pregnancy diagnosed with ultrasound (US) and treated with methods that successfully preserved the uterus. Gestational age, sonographic findings, means of conception, and method of treatment were recorded. RESULTS: Gestational age at diagnosis ranged from 5.0 to 7.9 weeks. Cardiac activity was documented in nine cases. Patients were treated as follows: transvaginal US-guided injection of potassium chloride into the embryo or gestational sac (n = 6), uterine artery embolization followed by dilation and evacuation (n = 4), dilation and evacuation after ligation of uterine artery branches (n = 1), and uterine artery embolization followed by administration of systemic methotrexate (n = 1). The cervical pregnancy was successfully ablated with one treatment in all cases. No patient required hysterectomy, and only one patient required transfusion. Two patients subsequently delivered healthy babies; three other patients have been able to conceive successfully. CONCLUSION: When cervical ectopic pregnancy is diagnosed early, US-guided termination or other conservative procedures allow preservation of the uterus, thus maintaining potential fertility.

Cervix Uteri↗
PubMed1994

Sonography of the fetal posterior fossa: false appearance of mega-cisterna magna and Dandy-Walker variant.

PURPOSE: To establish that incorrect scanning of the fetal posterior fossa may falsely create the appearance of a mega-cisterna magna (MCM) or Dandy-Walker variant (DWV). MATERIALS AND METHODS: After routine sonography, 100 consecutive fetuses (gestational age range, 25-40 weeks) without abnormality underwent additional posterior fossa scanning in an attempt to create the appearance of an MCM (anteroposterior diameter larger than 10 mm) or DWV. Sonograms were obtained in a plane inferior to or angled more coronally than the routine axial plane. RESULTS: The posterior fossa was depicted in 93 fetuses. Pseudo-MCM occurred in 35 (38%) of 93 fetuses: 12 (30%) of 40 fetuses aged 25.0-29.9 weeks, 11 (50%) of 22 fetuses aged 30.0-34.9 weeks, and 12 (39%) of 31 fetuses aged 35.0-40.0 weeks. Pseudo-DWV occurred in 40 (43%) of 93 fetuses: 20 (50%) of 40 fetuses aged 25.0-29.9 weeks, 12 (55%) of 22 fetuses aged 30.0-34.9 weeks, and eight (26%) of 31 fetuses aged 35.0-40.0 weeks. CONCLUSION: Sonography of the posterior fossa in an angled semi-coronal plane should be avoided because it may create an appearance that mimics an abnormality.

Artifacts↗
PubMed1994

Distal ureteral calculi: detection with vaginal US.

PURPOSE: To describe the use of vaginal ultrasonography to identify distal ureteral calculi and hydroureter. MATERIALS AND METHODS: Abdominal and vaginal sonography were performed in 13 women with distal ureteral calculi. Indications for sonography included flank pain, hematuria, and suspected appendicitis. Six patients were pregnant. RESULTS: In each patient, vaginal sonograms demonstrated a distal ureteral calculus; in only two cases was the calculus detected with transabdominal sonography. Distal hydroureter was identified with vaginal scanning in each patient but with abdominal scanning in only two. Hydronephrosis was absent in three patients, mild in six, and moderate in four. Symmetric ureteral jets were noted at transabdominal sonography in two of nine patients. Follow-up transvaginal scans obtained shortly after passage of stones in two patients revealed swelling of the trigone but normal ureteral jets. CONCLUSION: In symptomatic female patients, use of vaginal sonography should be considered to evaluate the distal ureter for calculi, particularly if the results of transabdominal examination are normal or inconclusive.

Adult↗
PubMed1994

Clinical significance of isolated fetal pericardial effusion.

Prenatal sonographic identification of a small rim of pericardial fluid, measuring less than 2 mm in thickness, is a normal finding. Pericardial fluid 2 mm or greater in thickness may be associated with structural anomalies or hydrops, but its clinical significance in the absence of these associated findings has not been evaluated. We assessed the outcome in fetuses with isolated pericardial effusions of at least 2 mm thick. Our study population included 52 fetuses with effusions ranging from 2 to 7 mm in thickness. We compared rates of preterm delivery, cesarean section, intrauterine growth retardation, perinatal complications, Apgar scores, and length of neonatal hospital stay in these 52 cases to the overall hospital rates and found no statistically significant difference. We conclude that in the absence of other sonographic abnormalities, the finding of a fetal pericardial fluid collection 2 to 7 mm in thickness is not associated with adverse outcome.

Female↗