From Big Medical Encyclopedia

GONIOTOMY, GONIOPUNCTURE (Greek gonia corner + tome section, section; lat. punctura a prick) — the surgeries in the field of an angle of iris (a corner of an anterior chamber of an eye) made at glaucoma. The starting moment in development of these surgical interventions was idea of an important pathogenetic role patol, the changes of an angle of iris at glaucoma leading to disturbance of normal outflow of intraocular liquid with the subsequent increase in intraocular pressure.

The goniotomy and a goniopuncture can be carried out is combined in the course of one intervention.

The goniotomy offered by Barkan (O. of Barkan) in 1936, was developed with a detailed orientation of intervention on certain structures of an angle of iris. Operation is shown at inborn glaucoma. It is desirable to carry out it within the first year of life of the child as further the idle venous sine of a sclera (helmets the channel) tends to be obliterated and recovery of normal outflow becomes impossible.

The goniotomy is made usually under direct direct vision for what on the operated eye the special operational gonioscopy lens (is located see. Gonioskopiya ), allowing the surgeon to see an angle of iris. Visibility of an angle of iris can be reached also by filling of an anterior chamber of an eye by air. At a muddy cornea the goniotomy can be made also without direct vision, however the results received at the same time it is much worse. The most exact section can be received with use of an operative microscope. Operation is made by a special knife — goniotomy, the offered Barkan. Goniotom has short (apprx. 2 mm) the edge passing into gradually extending long conic neck, edges plays a role of a stopper, closing the place of entry of the tool into an anterior chamber and interfering with the expiration of liquid from it during operation.

Fig. 1. Scheme of a goniotomy: the gonioscopy lens (it is specified by shooters) is imposed on a cornea, it is made in a stake goniotomy to the area of a limb, the tip of a goniotom is brought to a corner of an anterior chamber of an eye, the conjunctiva is fixed by tweezers.

At a goniotomy of eyes it has to be reliably fixed. After imposing of an operational gonioscopy lens on a cornea (usually in 1 — 2 mm from a limb on a horizontal meridian outside) stick in an anterior chamber gonioty. From here it will be out through an anterior chamber to its opposite side available to observation through a gonioscopy lens (fig. 1). Tip of a goniotom approximately on 0,5 mm kzad from a front boundary ring of Shvalbe, a kpereda from the basis of an iris stick from within in fabrics of a corner immediately. Displacing an edge in the parties, expand a cut to 1/4 — 1/3 circles of an angle of iris; at the same time the place in Coca in a cornea serves as if as a point of rotation. Excessively deep water of a cut is harmful. Upon completion of a cut the knife is quickly taken to avoid emptying of an anterior chamber; at the end of operation it is filled with air. After operation in a conjunctival sac dig in miotocs for the prevention of development of peripheral synechias in a root of an iris of the eye. At the correct technology of operation blood in an anterior chamber does not appear. In case of insufficient effect operation can be repeated in other quadrant of an angle of iris.

During the performance of operation at early children's age the frequency of successful outcomes reaches 75%. At usual glaucoma of adults the goniotomy is ineffective.

In 1956 Mr. Barkan offered a so-called cyclogoniotomy for treatment of glaucoma of adults. The equipment her same, as goniotomies, but a section in the field of a corner make a little kzada, in a zone of an attachment of a ciliary body (corpus ciliare) to a scleral spur. Efficiency of this operation in a wedge, practice was insufficient.

The goniopuncture offered in 1950 Mr. of Sheye (N. of Scheie), is fistuliziruyushchy operation.

Fig. 2. The scheme of a goniopuncture (at the left — in a section): after a puncture of a peripheral part of a cornea (1) it is entered gonioty (2) which made a puncture in the field of a corner of an anterior chamber of an eye; under a conjunctiva normal saline solution is previously entered into the area of a puncture (3.)

The goniopuncture is shown at inborn, and also at juvenile glaucoma, at a cut the goniotomy is usually inefficient, however results of a goniopuncture usually it is better for those, than the patient is younger. The equipment of a goniopuncture is in many respects similar to the equipment of a goniotomy. However at this operation make in the field of an angle of iris not a section, and perforation of a sclera in one point (fig. 2), in the field of a corneoscleral cover. The knife is turned on 90 ° around a longitudinal axis and taken. Not to damage a conjunctiva in a point of a vykol, under it enter 0,5 ml of isotonic solution of sodium chloride. Operation can be made with a contact lens and without it.

See also Hydrophthalmia , Glaucoma .

Bibliography: Kowalewski E. I. Children's ophthalmology, M., 1970; Krasnov. M. Mikrokhirurgiya of glaucomas, M., 1974, bibliogr.; The guide to eye surgery, under the editorship of M. L. Krasnov, M., 1976.

M. M. Krasnov.