Biomedical subjects

Maria L Vianna

Publications and source records attributed to Maria L Vianna.

3 recordsLinked to original sources

PubMed2006

Mechanical comparison of two knots and two crimp systems for securing nylon line used for extra-articular stabilization of the canine stifle.

OBJECTIVE: To compare mechanical properties of knotted and crimped nylon loops. STUDY DESIGN: In vitro mechanical evaluation. SAMPLE POPULATION: Loops of 27 kg-test nylon leader. Single strand-clamped square knot compared with 2 crimp systems. Two strand--self-locking knot compared with 2 crimped loops. METHODS: (a) Single pull to failure (n = 10) at 500 mm/min. Initial loop tension (N), peak load (N), peak elongation (mm), stiffness of the linear portion of the curve (N/mm), and failure mode were recorded. (b) Incremental cyclic loading to failure (n = 5)--each loop was cycled 5 times to 100 N at a loading rate of 200 mm/min. Cycling was repeated, with the load increased by 50 N after each set. Elongation (mm), tension remaining (N), and after permanent deformation was present, elongation at 10 N (mm) were measured. RESULTS: Initial tension and stiffness were greater for crimped loops when compared with knotted loops. There were no differences between crimped loops. The self-locking knot elongated more, and was less stiff, when compared with 2 crimped loops. With incremental loading, knotted loops elongated more than crimped loops. The tension remaining in the loop fell below 10 N more quickly for knotted loops compared with crimped loops. CONCLUSION: Crimped loops are stiffer, and resist both static and cyclic load more effectively before becoming permanently elongated, when compared with knotted loops. CLINICAL RELEVANCE: Stifle stability will be maintained more effectively by crimped nylon loops when compared with knotted loops.

Animals↗

PubMed2004

Double aortic arch in a dog.

Vascular ring anomalies are developmental anomalies of the thoracic great vessels resulting in complete or partial encircling of the esophagus and the trachea by a vascular ring formation. Persistent right aortic arch with left ligamentum arteriosum accounts for 95% of vascular ring anomalies in dogs. The dog in this report had a double aortic arch, which is a type 4 vascular ring anomaly. Double aortic arch is a rare congenital heart defect resulting from the improper development of the embryonic arches. The prognosis for dogs that have undergone surgery for correction of double aortic arches is generally regarded as poor. The dog in this report underwent surgery for correction of double aortic arches and recovered without dilation or motility disorders of the esophagus. Results indicate that small animals that undergo early surgical correction of double aortic arches with relief of esophageal constriction can have a good prognosis. To the authors' knowledge, there have been no previous reports of dogs that have survived long enough to be discharged from the hospital after surgical correction of double aortic arches.

Animals↗

PubMedDate not supplied

Atresia ani in the dog: a retrospective study.

Congenital anomalies of the rectum and anus are rare in dogs. The most frequently reported anomaly is atresia ani. Four types of atresia ani have been reported, including congenital anal stenosis (Type I); imperforate anus alone (Type II) or combined with more cranial termination of the rectum as a blind pouch (Type III); and discontinuity of the proximal rectum with normal anal and terminal rectal development (Type IV). An increased incidence was found in females and in several breeds, including miniature or toy poodles and Boston terriers. Surgical repair is the treatment of choice, but postoperative complications can occur, including fecal incontinence and colonic atony secondary to prolonged preoperative distension.

Anal Canal↗