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Biomedical subjects

D M Sherer

Publications and source records attributed to D M Sherer.

At least 55 records · Page 3Linked to original sources

Prenatal ultrasonographic diagnosis of conditions associated with potential umbilical cord compression.

The objective of this review is to assess the current literature pertaining to prenatal ultrasonographic diagnosis of various conditions that predispose the fetus to potential umbilical cord compression. We performed a MEDLINE search utilizing the terms:umbilical cord compression, nuchal cord, cord entanglement, and true knot. Additional sources were obtained through cross-referencing. Prenatal ultrasound assists in the diagnosis of nuchal cord(s), true knot of the umbilical cord, cord entanglement in monoamniotic twin gestations, and other unusual etiologies that may lead to umbilical cord compression. Supplementary ultrasonographic measures including color Doppler imaging, Doppler flow velocimetry, and possibly three-dimensional ultrasound may further prenatal diagnosis of these conditions. Doppler flow velocimetry may also assist in detecting impaired or deteriorating umbilical artery flow reflecting increasing cord compression prior to the onset of adverse and potentially nonreversible effects upon the fetus. Close fetal surveillance in cases further complicated by decreased fetal movements, decreased amniotic fluid volume, postdates, fetal growth restriction, and impaired umbilical artery Doppler flow velocimetry may assist in the management of such gestations. Although definitive prospective studies investigating neonatal outcome following prenatal ultrasonographic depiction of potential umbilical cord compression are not currently available, review of the literature suggests that increased fetal surveillance may be indicated in certain clinical conditions.

Animals↗

Transient marked atelectasis: an unusual complication of asthma in pregnancy.

We present an unusual case in which a patient with asthma presented with acute respiratory distress of acute onset, secondary to marked atelectasis of the right middle and lower lobes, which resolved within 24 hr following administration of increased doses of intravenous steroids, inhalation therapy (beta-agonists and steroids), and pulmonary physiotherapy. This transient occurrence responding to basic therapeutic measures was considered consistent with the release of a mucous plug which had caused the above obstruction and associated symptomatology and radiographic findings. This case illustrates and supports the practice of chest imaging in patients with atypical presentations of asthma and stresses the importance of pulmonary physiotherapy and bronchodilatory therapy as primary therapeutic agents in cases of mucous plug-associated atelectasis.

Adult↗

First-trimester nuchal translucency screening for fetal aneuploidy.

The objective was to review current literature pertaining to first-trimester nuchal translucency screening for fetal aneuploidy. To this goal, all manuscripts published in the English language regarding this topic obtained from a MEDLINE search for 1966 through November 1998 were selected and reviewed. Additional sources were identified through cross-referencing. Current widespread application of first-trimester ultrasonography has enabled accumulation of an increasing body of knowledge pertaining to early screening for fetal aneuploidy. Following initial reports, recent studies of large populations of patients (> 500 participants) at either high- or low-risk for fetal chromosomal abnormalities, demonstrate that nuchal thickness of > 3 mm between 10 and 14 weeks' gestation by either transabdominal or transvaginal ultrasonography may serve as screening tool for fetal aneuploidy. Sensitivity and specificity rates improve when first-trimester maternal serum free beta-human chorionic gonadotropin (hCG) and pregnancy associated plasma protein A (PAPP-A) levels are added to this ultrasonographic tool. Current data regarding nuchal translucency including: nomograms, repeatability, optimal timing of measurement, accuracy and effect of confounding factors upon this ultrasonographic measurement, pathophysiology, increased associated incidence of fetal cardiac anomalies, and arrhythmias as well as other structural anomalies, Doppler velocimetry, spontaneous subsequent miscarriage, implications of nuchal translucency in twin gestations, and effect upon performance of subsequent midtrimester maternal serum screening are presented.

Aneuploidy↗

Glanzmann's thrombasthenia in pregnancy: a case and review of the literature.

Glanzmann's thrombasthenia is a rare autosomal recessive bleeding disorder resulting from a deficiency of glycoprotein IIb-IIIa complex in platelets. The deficient complex normally mediates platelet aggregation by binding adhesive proteins, which form bridges between activated cells. Despite normal platelet counts, morphology, prothrombin, and activated thromboplastin times, Glanzmann's thrombasthenia is characterized by a prolonged bleeding time and a severe hemorrhagic mucocutaneous diasthesis. Pregnancy and delivery are rare in these patients and have been associated with a high risk of severe hemorrhage. We present an unusual case in which a primi-gravida patient with Glanzmann's thrombasthenia underwent an uneventful pregnancy and spontaneous vaginal delivery, following intrapartum intravenous administration of single-donor platelets. Subsequent late postpartum hemorrhage required intravenous transfusion of an additional unit of single-donor platelets. In addition, we review the literature pertaining to pregnancy and Glanzmann's thrombasthenia with an emphasis on intrapartum prophylactic management.

Adult↗

Utilization of real-time ultrasound on labor and delivery in an active academic teaching hospital.

OBJECTIVE: Ultrasound (US) is currently available on most if not all Labor and Delivery (L+D) services. Our objective was to survey utilization of real-time US on L+D in an active academic teaching hospital. STUDY DESIGN: Between April 1, and July 31, 1998, all US examinations performed for clinical purposes on patients presenting to L+D, were documented. Data collected included: gestational age, whether or not the patient was in labor, number of fetuses, and indication for US. All US examinations were performed by OB/GYN housestaff at the PGY 2-3 level, and fellows in Maternal-Fetal Medicine. Statistical analysis included Student's t-test and chi2 when appropriate, with p < 0.05 considered significant throughout. RESULTS: During the 4-month study period, 1316 patients delivered and 1363 were discharged from L+D, not in labor. Of 630 US examinations 31.64% (192 of 630) and 67.69% (418 of 630) were performed in laboring versus nonlaboring patients, respectively. Of all patients delivered during the study period, 14.5% (192 of 1316) underwent intrapartum US, and of all nonlaboring patients, 30.66% (418 of 1363) underwent US on L+D. The mean gestational age at the time of assessment was 37.32 +/- 4.23 weeks' versus 35.74 +/- 5.76 weeks' gestation, in laboring versus nonlaboring patients respectively, p < 0.05. Main indications for US in patients in labor were; fetal presentation in patients with spontaneous rupture of membranes (SROM) 34.4% (n = 66), confirmation of vertex presentation 20.3% (n = 39), preterm labor 12% (n = 23), multiple gestation 7.3% (n = 14), and malpresentation 7.3% (n = 14). Main indications for patients not in labor were; amniotic fluid index 15.8% (n = 66), SROM 15.6% (n = 65), postdates 9.8% (n = 41) placental location 9.6% (n = 40), and decreased fetal movement 9.3% (n = 39). Ultrasound-guided interventions included: all deliveries of multiple gestations (n = 9), version in nonlaboring patients (n = 10), and postpartum curettage for retained placental tissue in conjuction with severe early postpartum hemorrhage (n = 2). The incidences of each separate indication for US were significantly different between laboring versus nonlaboring patients, p < 0.05, respectively. CONCLUSION: US examination is performed in 15% of patients in labor and 31% of patients not in labor assessed on L+D, constituting a widely applied diagnostic tool in this environment.

Delivery, Obstetric↗

Transabdominal application of transvaginal transducer enhancing depiction of mature cystic teratoma at 34 weeks' gestation.

We present an unusual case in which a 36-year-old patient was referred for consultation due to increasing upper left abdominal pain at 35 weeks' gestation. Transabdominal ultrasonography disclosed an appropriate-for-gestational-age singleton, vertex-presenting fetus with normal anatomy. An unclear, complex, semisolid, semicystic mass was noted in the upper right abdomen. Due to the close proximity of the adnexal mass to the patient's abdominal wall, a high-frequency transvaginal transducer was applied transabdominally. Unlike the unclear images generated at conventional transabdominal ultrasonography, this application depicted a discrete mass with multiple characteristics consisting of calcifications, hair and fatty tissue, considered diagnostic of a mature cystic ovarian teratoma. The patient delivered spontaneously at 39 weeks' gestation. At 6 weeks' postpartum an elective laparotomy left ovarian cystectomy was performed and a mature cystic teratoma confirmed by pathology examination.

Abdomen↗

Automated cervical cytology: meta-analyses of the performance of the PAPNET system.

UNLABELLED: Our objective was to assess current knowledge regarding PAPNET (Neuromedical Systems, Inc.) automated cervical cytology screening methods and to assess the performance of this automated system in comparison with manual screening. To this goal, studies published in the English language regarding the PAPNET system, identified from a MEDLINE search through August 1998 were selected. Performance of the PAPNET system was assessed with various meta-analysis techniques, using the method of Mantel-Haenszel. In the primary screening modality, meta-analysis of the performance of the PAPNET system indicates that when compared with manual screening, the odds of obtaining a positive result were significantly greater. The Mantel-Haenszel odds ratio for combined studies was 1.19 (95 percent CI = 1.13 to 1.26, P < .001), corresponding to 20 percent greater odds of positive or suspicious slides with PAPNET system. The PAPNET system performs with almost two-fold less false-negative results. The Mantel-Haenszel odds ratio for combined studies was 0.41 (95 percent CI = 0.25 to 0.67, P < .005). Applied as a quality control modality rescreening all consecutive previously manually screened negative slides, depending on study design, the PAPNET system reclassified as abnormal between 0.1 and 5 percent. However, when the PAPNET system was used to rescreen known false-negative slides, PAPNET system rescreening can correctly identify between 20 and 90 percent of manually screened false-negative slides with an average reduction of 33 percent of the manually screened false-negative slides. We conclude that compared with manual screening, PAPNET identifies 20 percent more abnormal, has two-fold less false-negative, and reclassifies as abnormal one third of manually screened false-negative slides. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader will be able to understand how the PAPNET system works and what is its approved use by the FDA, and to understand the associated benefits and shortcomings of the PAPNET system when compared with the traditional screening method.

Cost-Benefit Analysis↗

Automated cervical cytology: meta-analyses of the performance of the AutoPap 300 QC System.

The objective of this study was to review current knowledge regarding the performance of the AutoPap 300 QC System (NeoPath Inc., Redmond, WA) for automated cervical cytology screening. To this goal, we identified all studies published in the English language that included the AutoPap 300 QC automated cervical cytology system. The studies were obtained from a MEDLINE search through October 1998; additional sources were identified through cross-referencing. Studies concerning the AutoPap 300 QC System containing complete data are presented descriptively. Meta-analyses about the performance of the AutoPap 300 QC System were performed. The central goal of the meta-analyses was to estimate the overall false-negative rate of the AutoPap 300 QC System when applied in either of the two following modalities: primary screening and quality control. Of the 14 studies concerning the performance of the AutoPap 300 QC System as a primary screening modality, four studies provided complete data about the number of abnormal slides, review rate, and number of slides selected. Meta-analysis of these four studies indicate sensitivities ranging between 85 and 100 percent. Regarding the performance of the AutoPap 300 QC System in the quality control modality, of the 14 studies reviewed, 5 studies provided complete data including the number of false-negatives, review rate, and number of slides selected. Meta-analysis of these five studies indicate an average sensitivity of the AutoPap 300 QC System applied as a rescreening modality of 37 percent (95% CI; 34-40 percent), with observed salvage ratios of between 3.5 and 5.6 when review rate of the AutoPap 300 QC System was set at 10 percent.

Female↗

Management of pelvic abscess during pregnancy: a case and review of the literature.

UNLABELLED: Cases of pelvic or abdominal abscess complicating pregnancy are rare. Noninvasive diagnostic techniques including ultrasonography, computed tomography (CT), and magnetic resonance imaging (MRI) have enabled early diagnosis of this unusual complication of pregnancy. We describe a patient in whom the diagnosis of a pelvic mass was made by sonography and MRI at 25 weeks' gestation. At laparotomy, a pelvic abscess was partially resected and drained. Two weeks later when the patient again became symptomatic, a recurrent pelvic abscess was detected by CT and treated with intravenous antibiotics and CT-guided transcatheter drainage. The patient's recovery was thereafter uncomplicated and she delivered a healthy male infant by elective repeat cesarean at 38 weeks' gestation. The literature concerning pelvic and abdominal abscesses during pregnancy is reviewed. The potential advantages of imaging-guided, percutaneous transcatheter drainage for the treatment of such patients are emphasized. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader will be able to understand the nonsurgical alternatives for the drainage of intraabdominal abscesses, the possible etiologies of intraabdominal abscess formation in the pregnant population, and the various approaches to percutaneous catheter drainage of intraabdominal abscesses.

Abscess↗

Transcatheter uterine artery embolization for the management of symptomatic uterine leiomyomas.

UNLABELLED: Transcatheter arterial embolization has been applied traditionally in obstetrics and gynecology for the emergency control of pelvic hemorrhage, usually after failure of conventional surgical measures. Pelvic trauma is the most common, nongynecologic etiology of uncontrollable pelvic hemorrhage requiring use of this hemostatic technique. Recently, elective transcatheter arterial embolization of uterine leiomyomas has been performed to decrease related symptomatology in an attempt to avoid surgical intervention. Our objective was to review current pertinent data regarding this new therapeutic modality. To this goal, all manuscripts published in the literature regarding this topic obtained from a MEDLINE search for 1966 through September 1998 were selected and reviewed. Additional sources were identified through cross-referencing. Currently, approximately 193 patients worldwide have been managed with this investigational procedure. Main indications include symptomatic uterine leiomyomata with menometrorrhagia, anemia, or pain. Success rates seem promising with a very low failure rate. This procedure results in significant (uterine and leiomyoma) volume reduction of between 20 and 80 percent. Postprocedural pain is common during the first day after the procedure, often requiring intravenous nonsteroidal antiinflammatory drugs and narcotic analgesia. Rare complications include endometritis, pyometra, and uterine necrosis, which may require hysterectomy. Reported follow-up time ranges between 6 and 60 months. Implications on subsequent fertility have not been established. Although successful pregnancies subsequent to this procedure have been reported, because of the unknown long-term effect of this procedure on fertility or perinatal outcome, this technique should not be performed when future fertility is desired. This review suggests that although not currently accepted as standard of care, transcatheter embolization of the uterine arteries can be considered as a nonsurgical technique for the management of appropriately selected patients. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians LEARNING OBJECTIVES: After completion of this article, the reader will be able to explain the current indications and contraindications of transcatheter uterine artery embolization of leiomyomas; to identify the various complications of the procedure and the type of embolic materials used; and to estimate the success rate of this procedure in the current literature.

Adult↗

Prenatal sonographic findings associated with sporadic subcortical nodular heterotopia.

BACKGROUND: Subcortical nodular heterotopia is a neuronal migration disorder of uncertain etiology. This disorder occurs primarily in females and has a familial X-linked dominant inheritance pattern. The predominant symptom associated with heterotopia is seizures. CASE: At 23 weeks' gestation, prenatal sonography disclosed an isoechoic supratentorial intracranial mass causing right-sided shift of midline structures and compression of the contralateral cerebral ventricle. Serial ultrasound examinations of this mass were significant for the absence of invasion into surrounding structures, gross enlargement of cranial biometric parameters, and hydrocephalus and hydrops fetalis. Neonatal magnetic resonance imaging findings were consistent with gray matter heterotopia and were confirmed as such by brain biopsy. CONCLUSION: Subcortical nodular heterotopia manifested unique prenatal sonographic findings. This case suggests the possibility of prenatal diagnosis in families at risk for this lesion.

Adult↗

Transvaginal sonography of the forewaters in the assessment of amniotic fluid volume in patients with oligohydramnios.

OBJECTIVE: To determine whether the forewaters should be considered in the assessment of amniotic fluid (AF) volume in patients beyond 37 weeks' gestation. METHODS: Sixty patients were prospectively studied and designated as having oligohydramnios or normal AF volume based upon on the standard four-quadrant AF index (AFI) of < or = 5 cm or > 5 cm, respectively. The distance between the internal os and the fetal head was measured transvaginally. This measurement was first added to the standard AFI and subsequently interchanged with the lowest of the two lower abdominal quadrant measurements. Statistical analysis included Student's t-test with p < 0.05 considered significant. RESULTS: Thirty patients were classified as oligohydramnios and 30 normal AF volume. The two subgroups did not differ as to maternal age, parity, gestational age at sonographic examination, incidence of meconium-stained amniotic fluid or 5-min Apgar scores < 7, or birth weight. No significant difference was noted between the mean forewaters measurement of patients with oligohydramnios and controls (0.2 +/- 0.1 and 0.4 +/- 0.1 cm, respectively). In patients with oligohydramnios, there was no significant difference between the standard AFI and the AF volume with the forewaters in each of the methods assessed (2.7 +/- 0.3, 2.9 +/- 0.3, and 2.7 +/- 0.3 cm, respectively). CONCLUSION: We conclude that various permutations of the AFI, which include sonographic assessment of the forewaters, do not impact on the diagnosis of oligohydramnios.

Abdomen↗

Prenatal diagnosis of sirenomelia with bilateral hydrocephalus: report of a previously undocumented form of VACTERL-H association.

Sirenomelia represents a severe developmental field defect of the posterior axis caudal blastema, resulting in partial or complete fusion of the lower limb buds. The VATER association is a combination of morphological defects including vertebral defects, anal atresia, tracheoesophageal fistula, esophageal atresia, radial and renal anomalies. The VACTERL-H association is a rare expanded form of the VATER association that includes cardiac defects, limb defects, and hydrocephalus. It has been suggested that the VATER association may represent a less severe form of sirenomelia. In this report, we document a case in which prenatal ultrasonography detected simultaneously occurring sirenomelia and hydrocephalus. Postmortem radiography and autopsy findings confirmed the prenatal diagnosis. To our knowledge, this is the first report of prenatal diagnosis of a fetus with these two abnormalities. This report supports the hypothesis that VATER association, VACTERL-H association, and sirenomelia may represent pathophysiologically related entities.

Adult↗

Nonimmune hydrops fetalis due to congenital syphilis associated with negative intrapartum maternal serology screening.

We present an unusual case, in which a woman presenting with markedly decreased fetal movements at 29 weeks gestation following a recent increase in fundal height was noted sonographically to have fetal hydrops consisting of scalp edema, marked hepatomegaly, ascites, and polyhydramnios. No lethal structural congenital anomaly was noted. Admission laboratory examinations revealed a negative antibody screen and a negative RPR. Emergent cesarean section was performed due to prolonged fetal bradycardia during biophysical profile testing. The acidotic hydropic neonate weighing 1825 g was resuscitated yet succumbed at 3 hr of life following intravenous administration of antibiotics. Neonatal blood was RPR positive at 1:16. Postmortem pathology examination demonstrated severe multiorgan system failure secondary to overwhelming congenital syphilis. Extensive extramedullary hematopoiesis was noted and histopathology with Dieterle stains revealed numerous hepatic spirochetes. Postpartum reexamination of the maternal blood with serial dilutions revealed a positive RPR at 1:1024. This case emphasizes that initial negative screening for syphilis may be seen despite overwhelming infection, a condition that has been termed the "prozone effect."

Adult↗

Prenatal ultrasonographic diagnosis of fetal intracranial tumors: a review.

Our objective was to review current literature pertaining to prenatal ultrasonography of various fetal intracranial neoplastic and non-neoplastic tumors. To this goal, all manuscripts published in the English language regarding this topic obtained from a MEDLINE search from 1966 through January 1998 were selected and reviewed. Additional sources were identified through cross-referencing. Intracranial fetal tumors are extremely rare and precise diagnosis is dependent on histology examination of tissue obtained at subsequent surgery or autopsy. Currently, prenatal ultrasonographic findings associated with the following fetal intracranial tumors have been described: teratomas; neuroepithelial tumors including: glioblastoma, astrocytoma, gangliocytoma, medulloblastoma, choroid plexus, and papilloma; and mesenchymal tumors. Non-neoplastic fetal intracranial tumors are even less frequent and include: unilateral megalencephaly, heterotopia, and lipoma of the corpus callosum. Cardinal ultrasonographic findings associated with fetal intracranial tumors include: echogenic and semicystic space occupying lesions with or without distortion of normal symmetrical intracranial (usually midline) structures, calcifications, craniomegaly, polyhydramnios, obstructive hydrocephaly, high-output cardiac failure (hydrops fetalis), the presence of other associated structural anomalies, and infrequently abnormal cerebral Doppler flow velocimetry.

Astrocytoma↗