Healon

Description

The Healon® Ophthalmic Viscosurgical Device (OVD) is a sterile, nonpyrogenic, viscoelastic preparation of a highly purified, noninflammatory, high molecular weight fraction of sodium hyaluronate.The Healon OVD contains 10 mg/mL of sodium hyaluronate dissolved in physiological sodium chloride phosphate buffer (pH 7.0-7.5).This high molecular weight polymer is made up of repeating disaccharide units of N-acetyl-glucosamine and sodium glucuronate linked by ß 1-3 and ß 1-4 glycosidic bonds.

Characteristics

Sodium hyaluronate is a physiological substance that is widely distributed in the extracellular matrix of connective tissues in both animals and man. For example, it is present in the vitreous and aqueous humor of the eye, the synovial fluid, the skin and the umbilical cord. Sodium hyaluronates prepared from various human and animal tissues are not chemically different from each other.

The Healon OVD is a specific fraction of sodium hyaluronate developed as an ophthalmosurgical aid for use in anterior segment and vitreous procedures. It is specific in that:

1. It has a high molecular weight.
2. It is reported to be nonantigenic1.6.
3. It does not cause inflammatory2 or foreign body reactions.
4. It has a high viscosity.

Furthermore, the 1% solution of the Healon OVD is transparent, is reported to remain in the anterior chamber for less than 6 days3 and protects corneal endothelial cells4.5 and other ocular structures.The Healon OVD does not interfere with epithelialization and normal wound healing.

Indications

Uses

The Healon OVD is indicated for use as a surgical aid in cataract extraction (intra- and extracapsular), IOL implantation, corneal transplant, glaucoma filtration and retinal attachment surgery.

In surgical procedures in the anterior segment of the eye, instillation of the Healon OVD serves to maintain a deep anterior chamber during surgery, allowing for efficient manipulation with less trauma to the corneal endothelium and other surrounding tissues.

Furthermore, its viscoelasticity helps to push back the vitreous face and prevent formation of a postoperative flat chamber.

In posterior segment surgery the Healon OVD serves as a surgical aid to gently separate, maneuver and hold tissues.The Healon OVD creates a clear field of vision thereby facilitating intra- and post-operative inspection of the retina and photocoagulation.

Dosage And Admintisration

Applications

Cataract Surgery – IOL Implantation

A sufficient amount of the Healon OVD is slowly, and carefully introduced (using a cannula or needle) into the anterior chamber.

Injection of the Healon OVD can be performed either before or after delivery of the lens. Injection prior to lens delivery will, however, have the additional advantage of protecting the corneal endothelium from possible damage arising from the removal of the cataractous lens5.The Healon OVD may also be used to coat surgical instruments and the IOL prior to insertion.

Additional Healon OVD can be injected during surgery to replace any Healon OVD lost during surgical manipulation (see PRECAUTIONS section).

Glaucoma Filtration Surgery

In conjunction with performing of the trabeculectomy, the Healon OVD is injected slowly and carefully through a corneal paracentesis to reconstitute the anterior chamber. Further injection of the Healon OVD can be continued allowing it to extrude into the subconjunctival filtration site and through and around the sutured outer scleral flap.

Corneal Transplant Surgery

After removal of the corneal button, the anterior chamber is filled with the Healon OVD.The donor graft can then be placed on top of the bed of Healon OVD and sutured in place.Additional Healon OVD may be injected to replace the Healon OVD lost as a result of surgical manipulation (see PRECAUTIONS section).The Healon OVD has also been used in the anterior chamber of the donor eye prior to trepanation to protect the corneal endothelial cells of the graft5.

Retinal Attachment Surgery

The Healon OVD is slowly introduced into the vitreous cavity. By directing the injection, the Healon OVD can be used to separate membranes (e.g. epiretinal membranes) away from the retina for safe excision and release of traction.The Healon OVD also serves to maneuver tissues into the desired position, e.g. to gently push back a detached retina or unroll a retinal flap, and aids in holding the retina against the sclera for reattachment.

Instructions

Sterile Opening Technique

Tear off the paper covering.

Bend the plastic backwards at the central indentation so as to fully expose the white plastic rod.

Dislodge syringe and place onto sterile field.

 

 

Assembly

 

 

Press the vial completely into the holder so that the needle perforates the membrane.

Important

Perforate the membrane before screwing on the plastic rod.

 

 

Remove the plastic rod.

 

 

Screw the plastic rod into the blue plunger.

 

 

Connect the cannula and check for proper function.

Store at 2 to 8°C (36 to 46°F). For single use only

How Supplied

The Healon OVD is a sterile, nonpyrogenic, viscoelastic preparation supplied in disposable glass syringes, delivering 0.85 mL, 0.55 mL or 0.4 mL sodium hyaluronate (10 mg/mL) dissolved in physiological sodium chloride phosphate buffer (pH 7.0-7.5). Each mL of Healon OVD contains 10 mg of sodium hyaluronate, 8.5 mg sodium chloride, 0.28 mg of disodium hydrogen phosphate dihydrate, 0.04 mg of sodium dihydrogen phosphate dihydrate and q.s. water for injection U.S.P.The Healon OVD syringes are terminally sterilized and aseptically packaged.

A sterile single-use 27 G cannula is enclosed in the 0.4 mL, 0.55 mL, and 0.85 mL boxes.

Refrigerated Healon OVD should be allowed to attain room temperature (approximately 30 minutes) prior to use.

For intraocular use.

Store at 2 to 8°C (36 to 46°F).
Protect from freezing.
Protect from light.

Caution

Federal law restricts this device to sale by or on the order of a physician.

Definition of symbols on cannula, syringe-, blister label and carton.

 

 

REFERENCES

1. Richter,W., Ryde, M. & Zetterström, O.: Nonimmunogenicity of a purified sodium hyaluronate preparation in man. Int Arch Appl Immun 59:45-48 (1979).

2. Balazs, E.A.: Ultrapure hyaluronic acid and the use thereof. U.S. Patent 4, 141, 973 (1979).

3. Balazs, E.A., Miller, D & Stegmann, R.:Viscosurgery and the use of Na-hyaluronate in intraocular lens implantation. Lecture, Cannes, France (1979).

4. Miller, D. & Stegmann, R.: Use of Na-hyaluronate in anterior segment eye surgery. Am Intra-Ocular Implant Soc J 6 (1980b) p 13-15.

5. Pape, L.G. & Balazs, E.A.:The use of sodium hyaluronate (Healon®) in human anterior segment surgery. Ophthalmol 87 (1980) p 699-705.

6. Richter,W.: Non-immunogenicity of purified hyaluronic acid preparations tested by passive cutaneous anaphylaxis. Int Arch All 47 (1974) p 211-217.

Manufactured by: AMO Uppsala AB, Rapsgatan 7, Box 6406, SE-751 36 Uppsala, Sweden. Revised: May 2014

Side Effects

The Healon OVD is extremely well tolerated after injection into human eyes. A transient rise of intraocular pressure postoperatively has been reported in some cases.

In posterior segment surgery intraocular pressure rises have been reported in some patients, especially in aphakic diabetics, after injection of large amounts of the Healon OVD.

Rarely, postoperative inflammatory reactions (iritis, hypopyon) as well as incidents of corneal edema and corneal decompensation have been reported. Their relationship to the Healon OVD has not been established.

Drug Interactions

No information provided.

WarningS

Included as part of the PRECAUTIONS section.

Precautions

Those normally associated with the surgical procedure being performed.

Overfilling the anterior or posterior segment of the eye with the Healon OVD may cause increased intraocular pressure, glaucoma, or other ocular damage.

Postoperative intraocular pressure may also be elevated as a result of preexisting glaucoma, compromised outflow and by operative procedures and sequelae thereto, including enzymatic zonulysis, absence of an iridectomy, trauma to filtration structures, and by blood and lenticular remnants in the anterior chamber. Since the exact role of these factors is difficult to predict in any individual case, the following precautions are recommended:

• Don’t overfill the eye chambers with the Healon OVD (except in glaucoma surgery – See Applications section).
• In posterior segment procedures in aphakic diabetic patients special care should be exercised to avoid using large amounts of the Healon OVD.
• Remove some of the Healon OVD by irrigation and/or aspiration at the close of surgery (except in glaucoma surgery – See Applications section).
• Carefully monitor the intraocular pressure, especially during the immediate postoperative period. If significant rises are observed, treat with appropriate therapy.

Care should be taken to avoid trapping air bubbles behind the Healon OVD.

Because the Healon OVD is a highly purified fraction extracted from avian tissues and is known to contain minute amounts of protein, the physician should be aware of potential risks of the type that can occur with the injection of any biological material.

Because of reports of an occasional release of minute rubber particles, presumably formed when the diaphragm is punctured, the physician should be aware of this potential problem. Express a small amount of the Healon OVD from the syringe prior to use, and carefully examine the remainder as it is injected.

Reprocessed cannulas should not be used.

Sporadic reports have been received indicating that the Healon OVD may become ”cloudy” or form a slight precipitate following instillation into the eye.The clinical significance of these reports, if any, is not known since the majority received to date do not indicate any harmful effects on ocular tissues.The physician should be aware of this phenomenon and, should it be observed, remove the cloudy or precipitated material by irrigation and/or aspiration.

In vitro laboratory studies suggest that this phenomenon may be related to interactions with certain concomitantly administered ophthalmic medications.

Use only if solution is clear.

Overdose

No information provided.

Contraindications

At present there are no known contraindications to the use of the Healon OVD when used as recommended.

Clinical Pharmacology

No information provided.