PubMed Health⌕ Search

Biomedical subjects

F C Laing

Publications and source records attributed to F C Laing.

At least 19 recordsLinked to original sources
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

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↗
PubMed1992

Ultrasonography of the acute abdomen.

During the past decade, noninvasive imaging has assumed an increasingly prominent role in the evaluation of patients who have acute abdominal conditions. Ultrasonography is often the initial diagnostic imaging modality used to examine patients who are clinically suspected of having acute cholecystitis, choledocholithiasis, and acute appendicitis. This article focuses on the clinical considerations and the ultrasonographic findings that relate to each of these conditions. In addition to describing the ultrasonographic appearances for each of these entities, this article also emphasizes useful scanning techniques that will provide optimal images.

Abdomen, Acute↗
PubMed1992

Ultrasound of gynecologic pathologies.

Since the introduction of vaginal transducers and color Doppler ultrasound, there has been renewed interest in evaluating the female pelvis. Several recently published manuscripts presented convincing material that suggests benign and malignant ovarian and uterine pathologies can be distinguished from each other on the basis of their vascularity. Duplex Doppler signals obtained from malignant tumors tend to demonstrate a low resistance pattern with continuous blood flow throughout the cardiac cycle. Benign lesions, in contrast, tend to display a more resistive pattern. The role of ultrasound in pediatric gynecologic conditions has also been nicely summarized in several recent papers. These are also discussed.

Adult↗
PubMed1990

Sonographic diagnosis of perforation in patients with acute appendicitis.

The sonographic diagnosis of appendicitis can be challenging in patients with perforation. In order to detect the accuracy of specific sonographic features of appendiceal perforation, graded compression sonograms in 100 patients with surgically confirmed acute appendicitis were reviewed retrospectively. Twenty-two of these patients had perforation. A statistically significant association was found between three sonographic findings and perforation: loculated pericecal fluid, prominent pericecal fat, and circumferential loss of the submucosal layer of the appendix. No single finding had a specificity greater than 59%. By using a combination of one or more findings, the overall sensitivity of sonography for the diagnosis of perforation was 86%. The specificity, however, was only 60%. Our results suggest that in patients without a sonographically visible appendix, recognition of loculated pericecal fluid and prominent pericecal fat may be a useful indirect clue to the diagnosis of perforating appendicitis.

Acute Disease↗
PubMed1989

Abdominal lymphoma in AIDS: evaluation with US.

The sonographic findings in 38 patients with abdominal lymphomas related to acquired immunodeficiency syndrome (AIDS) were reviewed. Thirty-three patients had non-Hodgkin lymphoma, and five had Hodgkin disease. Abnormal masses were detected with sonography in 33 patients (87%). Focal hypoechoic liver lesions up to 10 cm in diameter were visible in 17 patients. Several lesions were anechoic and septated, mimicking fluid. Adenopathy (at the retroperitoneum, mesentery, or porta hepatis) was seen in 15 patients. Other involved areas included bowel, omentum, spleen, kidney, and adrenal gland. AIDS-related abdominal lymphomas frequently cause extranodal masses that can be readily imaged with ultrasound. Ultrasound-guided fine needle aspiration biopsy allows a specific diagnosis to be made in many cases.

Abdominal Neoplasms↗
PubMed1989

Sonography in patients with suspected acute appendicitis: value in establishing alternative diagnoses.

We reviewed the clinical and sonographic findings in 297 patients who had graded compression sonography for suspected acute appendicitis. The purpose of the study was to determine the accuracy of sonography in detecting other diseases in the 174 patients in this group who proved not to have acute appendicitis. Of the 174 patients without acute appendicitis, 93 patients (53%) were ultimately discharged with a diagnosis of abdominal pain of unknown origin. Of the 81 patients in whom specific diagnoses were established, sonography suggested the correct diagnosis in 57 patients (70%). A broad spectrum of diseases was detected, including: gynecologic diseases (35); visceral diseases, including hollow viscera and diseases of liver, pancreas, or spleen (18); and urinary tract abnormalities (four). This study suggests that sonography is useful in establishing alternative diagnoses in patients undergoing sonography for suspected acute appendicitis.

Acute Disease↗
PubMed1989

Scrotal ultrasonography and the management of testicular trauma.

The early surgical repair of testicular injuries has reduced morbidity and increased testicular salvage. Orchiectomy can be avoided in about 90 per cent of cases. Ultrasound has increased our ability to diagnose parenchymal injury preoperatively and thus to advise the frightened patient more authoritatively and assure ourselves of the necessity of surgical exploration. In most cases, the patient can expect a short convalescence and preservation of his injured gonad.

Equipment Design↗
PubMed1989

Sonourethrography in the evaluation of urethral stricture disease.

Ultrasonography of the anterior urethra offers a dynamic three-dimensional study that can easily be repeated. It holds the promise of defining accurately, not only the exact length and severity of the strictured urethral segment, but also the extent of urethral fibrosis and the anatomy of the periurethral structures. A significant reduction in the incidence of recurrent stricture may be obtained by selecting patients for treatment on the basis of the findings of sonourethrography. Moreover, the potential exists for the use of this imaging method during internal urethrotomy to ensure a more accurate and aggressive incision of the stricture.

Humans↗
PubMed1988

Sonourethrography in the evaluation of urethral strictures: a preliminary report.

A total of 17 patients with suspected stricture disease underwent conventional retrograde urethrography and sonourethrography. When the length of the stricture as assessed by each imaging modality was compared to measurements at open urethroplasty in 7 patients, sonourethrography was consistently more accurate. Distension of the urethra with saline during the ultrasound examination enabled classification of the degree of spongiofibrosis, which was confirmed by full depth biopsy in 5 patients. Sonourethrography cannot adequately image the posterior urethra, even when the transcrotal approach is used. However, because it is a dynamic 3-dimensional study and can be repeated without risk of radiation exposure, sonourethrography is preferable to radiographic retrograde urography to evaluate patients with suspected anterior urethral strictures.

Humans↗
PubMed1988

Acute appendicitis: sonographic criteria based on 250 cases.

Two hundred and fifty consecutive patients with suspected appendicitis were examined with graded compression sonography. The initial diagnostic criterion for appendicitis was visualization of a noncompressible appendix; this was later modified to include the dimensions of the visualized appendix. The appendix was visualized in 91 of 250 patients (36%). Five adult patients with sonographically visible appendixes that were 6 mm or less in maximal diameter had either benign clinical follow-up (three patients) or a histologically normal appendix removed at surgery (two patients). However, two patients with appendixes measuring 6 mm in diameter and multiple appendicoliths had surgically confirmed acute appendicitis. Of 84 patients with visible appendixes measuring greater than 6 mm in maximal diameter, 78 had surgically confirmed acute appendicitis. In the remaining six, symptoms resolved spontaneously, and no surgery was required. In the absence of compelling clinical findings or an appendicolith, adult patients with maximal appendiceal diameters of 6 mm or less should undergo a period of close observation rather than immediate surgery. A diagnosis of appendicitis can be made in adult patients with persistent right lower quadrant pain and a visualized appendix greater than 6 mm in diameter.

Acute Disease↗