Valve Of Hasner Research Articles

Acquired Partial Nasolacrimal Obstruction due to a Suture Stent Following Esophagocolostomy

Nasolacrimal obstruction in children is usually congenital and typically results from stenosis at the valve of Hasner. Epiphora secondary to acquired dacryostenosis is much less common. We treated a child with partial, reversible, nasolacrimal obstruction from an unusual cause, a silk suture stent used to facilitate esophageal dilation following esophagocolostomy. Report of a Case. —Esophageal atresia without tracheoesophageal fistula was diagnosed in a 5-day-old boy. A feeding gastrostomy was placed, which functioned satisfactorily until the child underwent an esophagocolostomy (interposition of a segment of colon between the pharynx and the stomach) at age 14 months. Postoperative stenosis of the neoesophagus required expansion with Tucker dilators on several occasions during the following year. For this procedure, an indwelling No. 2 silk suture was used as a guide wire stent (Fig 1); the suture passed through the nostril, nasal cavity, and nasopharynx, down through the esophagocolostomy, and exited through an external gastrostomy

THE MANAGEMENT OF PEDIATRIE LACRIMAL PROBLEMS

The most common cause of tearing in the pediatric age group is blockage of the distal end of the nasolacrimal duct at the valve of Hasner. Evaluation with fluorescein using the dye disappearance test and the primary dye test, although not always as accurate as in adults, is possible. Conservative treatment is attempted initially followed by probing and, if necessary, silicone intubation. Less common causes of tearing are punctal atresia and congenital lacrimal sac fistula, which are usually diagnosed later, requiring opening of the atretic membrane and excision of the fistula tract, respectively. Amniotoceles are usually seen within a week of birth and are treated aggressively with medication and/or probing to prevent acute dacryocystitis.

Pleural Effusions and Pulmonary Edema

Pleural effusions are a common clinical problem, yet the mechanisms of pleural fluid formation have only recently been investigated. In this article, the anatomy and physiology of the normal pleural space is discussed, as well as the pathophysiology of pleural effusion formation.

Echographic diagnosis in diseases of the efferent tear ducts

We report the results of our echographic examinations of 250 patients with diseases of the lacrimal drainage system. First, normal A- and B-scan pictures are presented. Then the echographic criteria of malformations (persistence of the valve of Hasner, dacryocystocele), dacryocystitis and its complications (fistula, membrane-formation, stenosis) are discussed. The possibility of pre- and postoperative controls with echography is stressed. Tumors of the lacrimal sac can also easily be detected.

Lacrimal scintigraphy. III. Physiological aspects of lacrimal drainage.

Lacrimal scintigraphy (LS) was performed on asymptomatic lacrimal drainage systems and the results were evaluated to understand the physiology of lacrimal drainage. It was found that a physiological obstruction can exist at the level of the nasolacrimal duct in normal asymptomatic individuals, and it is suggested that this obstruction is due to the resistance offered by the valve of Hasner, which in turn is dependent on (a) the volume of fluid in the lacrimal sac and the nasolacrimal duct, and (b) the anatomical integrity of the valve. The LS observations are taken into account to postulate a mechanism of drainage from the lacrimal sac into the nose, which hitherto has not been very clear. It is also suggested that reflux can occur between the various compartments of the lacrimal drainage system and that the various valves in the membranous passageway can become incompetent in an obstructed system.

Lacrimal air anomalies.

It is a curious fact that air, except in minimal amounts, is not often found in the lacrimal sac, despite its anatomic connection with the nose. One of the earliest tests (1823) for patency of the lacrimal passages was to have the patient blow the nose and feel or hear the exit of air from the lacrimal puncta; this, however, does not hold in most persons. According to Duke-Elder,1about 5% of persons can whistle through their eyes, as it were, when air is forcibly exhaled with the nose closed, and some can emit smoke in the same manner. The nasolacrimal duct is an irregular passage lined with mucous membrane which has a variable number of folds, or valves, the function of which is uncertain. The fold at the lower orifice of the nasolacrimal duct, known as the valve of Hasner, is thought to be a barrier to the