David L Bolender | PubMed Health

PubMed2005

Preliminary investigation of the use of high frequency ultrasound imaging in the chick embryo.

BACKGROUND: The purpose of this study was to investigate the feasibility of using high frequency ultrasound to study the chick embryo in a noninvasive and longitudinal fashion. METHODS: A total of 10 SPF White Leghorn chick embryos (GDs 11-17; Hamburger and Hamilton stage 37-43) were consecutively examined with a GE Logiq 400 ProSeries ultrasound unit using an 11-MHz small parts ultrasound probe. Access for ultrasound visualization of the embryos was accomplished by opening a 2-3-cm window either in the air cell over the blunt end of the egg or laterally over the embryo-dependent side of the egg. Warmed ultrasound coupling gel was used for imaging, and thermal regulation was maintained with infant heel warmers. The ultrasound images were recorded directly on digital video using a Sony TRV 900 DV camcorder. The images were directly converted to jpeg and mjeg2 files for further analysis. RESULTS: Effective visualization of each embryo was possible on each day of the study period. The embryos were best visualized through the opening made in the air cell at the blunt end of the egg. The extent of the anatomic survey of the chick embryo was dependent upon the position of the embryo in the egg relative to the opening in the air cell. Doppler color flow mapping studies were obtained of the embryonic and extraembryonic circulation. CONCLUSIONS: This preliminary investigation clearly shows the feasibility of high frequency ultrasound imaging to study chick embryo development in a longitudinal and noninvasive fashion. Further studies are presently ongoing regarding earlier embryo development, as well as to determine the stability and dynamics of the methodology.

Animals↗

PubMed2002

Pyriform sinus malformations: a cadaveric representation.

BACKGROUND/PURPOSE: The most important aspects in management of pyriform sinus malformations are awareness of the diagnosis, familiarity with the clinical manifestations, and complete surgical excision of the entire tract. Pyriform sinus anomalies are the least common branchial apparatus malformations and present anatomically as sinus tracts with or without cystic dilatation. The clinical presentations can include lateral neck mass, thyroid abscess, suppurative thyroiditis, retropharyngeal abscess, neonatal airway obstruction, and even carcinoma. Recurrent symptoms after surgery suggest incomplete identification and excision of the tract. METHODS: Cadaveric dissections were performed to show both the proposed embryologic course and clinical manifestations of third and fourth branchial apparatus pyriform sinus anomalies. RESULTS: Illustrations and digital camera images of the cadaveric models are presented to explain the course of pyriform sinus fistula tracts. CONCLUSIONS: The authors discuss 3 case presentations of pyriform sinus anomalies with emphasis on their proposed embryologic origin and anatomic basis for surgical management. Surgical excision is the mainstay of therapy. Understanding the embryologic basis for pyriform sinus malformations aids in recognition of the diagnosis despite the myriad of clinical presentations. Laryngoscopy with sinus cannulation facilitates removal of the entire sinus tract with preservation of the recurrent and superior laryngeal nerves.

Abscess↗