Ophthalmic Devices; Reclassification of Neodymium:Yttrium: Aluminum:Garnet (Nd:YAG) Laser for Peripheral Iridotomy

DEPARTMENT OF HEALTH AND HUMAN SERVICES

Food and Drug Administration

21 CFR Part 886

[Docket No. 93P-0277]

Ophthalmic Devices; Reclassification of Neodymium:Yttrium:

Aluminum:Garnet (Nd:YAG) Laser for Peripheral Iridotomy

AGENCY: Food and Drug Administration, HHS.

ACTION: Proposed rule; notice of panel recommendation.

-----------------------------------------------------------------------

SUMMARY: The Food and Drug Administration (FDA) is proposing to

reclassify the ophthalmic neodymium:yttrium:aluminum:garnet (Nd:YAG)

laser (mode-locked or Q-switched) intended for peripheral iridotomy

from class III (premarket approval) into class II (special controls).

The agency is also issuing for public comment the recommendation of the

Ophthalmic Devices Panel (the Panel) regarding the reclassification of

this device. The Panel made this recommendation after reviewing the

reclassification petition submitted by Intelligent Surgical Lasers,

Inc. (ISL). FDA is also issuing for public comment its tentative

findings on the Panel's recommendation and its intent to change the

generic designation of the device from Nd:YAG laser for posterior

capsulotomy to Nd:YAG laser for posterior capsulotomy and peripheral

iridotomy. After considering any public comments on the Panel's

recommendation and FDA's tentative findings, FDA will approve or deny

the reclassification petition by order in the form of a letter to the

petitioner. FDA's decision on the petition will be announced in the

Federal Register. If the petition is approved and the device is

reclassified into class II, FDA will publish a final rule to codify the

reclassification.

DATES: Written comments by June 6, 1996.

ADDRESSES: Submit written comments to the Dockets Management Branch

(HFA-305), Food and Drug Administration, 12420 Parklawn Dr., rm. 1-23,

Rockville, MD 20857.

FOR FURTHER INFORMATION CONTACT: Morris Waxler, Center for Devices and

Radiological Health (HFZ-460), Food and Drug Administration, 9200

Corporate Blvd., Rockville, MD 20850, -301-594-2018.

SUPPLEMENTARY INFORMATION:

I. Introduction

On March 2, 1993, ISL submitted a petition under section 513(f)(2)

of the Federal Food, Drug, and Cosmetic Act (the act) (21 U.S.C.

360c(f)(2)), requesting that the ophthalmic Nd:YAG laser (mode-locked

or Q-switched) intended for peripheral iridotomy be reclassified from

class III into class II.

The subject device is automatically classified into class III under

section 513(f)(1) of the act because it is not within a type of device

that was introduced or delivered for introduction into interstate

commerce for commercial distribution before May 28, 1976, it is not

substantially equivalent to such a device, and it is not substantially

equivalent to a device placed in commercial distribution since May 28,

1976, which was subsequently reclassified into class II or class I.

Section 513(f)(2) of the act provides that FDA may initiate the

reclassification of a device classified into class III under section

513(f)(1) of the act, or the manufacturer or importer of the device may

petition the agency to reclassify the device into class I or class II.

FDA's regulations in 21 CFR 860.134 set forth the procedures for filing

and review of a petition to reclassify these class III devices. In

order to reclassify the ophthalmic Nd:YAG laser (mode-locked or Q-

switched) for peripheral iridotomy into class II, it is necessary that

the proposed new class has sufficient regulatory controls to provide

reasonable assurance of the safety and effectiveness of the device for

its intended use.

II. Background

Nd:YAG lasers originally were developed for industrial

applications, and were successfully employed in such industries as

watchmaking prior to the initiation of clinical trials in Europe and

the United States. Therefore, the basic principles of operation of the

device

[[Page 9374]]

were scientifically established well before any clinical testing of the

device in ophthalmic surgery. -

Surgical iridectomies, i.e., manual surgical excisions of part of

the iris, were performed, with mixed results, in the late 1800's to

relieve the symptoms of glaucoma. In 1920, the differences between the

various types of glaucoma were described and it then became apparent

why the surgery relieved the symptoms of some patients and not others.

As a result, peripheral surgical iridectomies were then performed only

on patients with pupillary-block (angle-closure) glaucoma.

Argon laser iridotomies, surgery with an argon laser to create an

iris hole, became the preferred treatment for most cases of angle-

closure glaucoma in the 1970's. Although there were advantages to the

use of argon lasers (reduced risk of flat chamber, wound leak,

endophthalmitis, malignant glaucoma, and lens subluxation), there were

different complications associated with the new modality (permanent

corneal burns, retinal burns, iritis, localized cataract formation,

posterior synechiae, failed patency, intraocular pressure (IOP) rises

and iris pigmentation).

The next treatment modality, iridotomy with the Q-switched Nd:YAG

laser, was introduced during the early 1980's to treat angle-closure by

a mechanical cutting effect to create peripheral iridotomies rather

than the thermal effect of argon lasers. Because the technology

permitted tissue disruption through a transparent medium with

negligible heat generation, the Nd:YAG laser appeared to be ideal for

ophthalmic surgery on opacified posterior capsular membranes, thus

avoiding the risks involved in traditional invasive surgery as well as

the thermal effects characteristic of other ophthalmic laser devices.

Clinical trials were conducted and, subsequently, FDA granted premarket

approval for three CooperVision Nd:YAG lasers (models 2000 and 2500 in

1985; model 2300 in 1986) for discission of the posterior capsule of

the eye (posterior capsulotomy).

On January 24, 1986, the Medical Laser Manufacturers Association

(MLMA) submitted to FDA, under section 513(e) of the act and 21 CFR

860.120, a petition for a change in the classification of the

ophthalmic Nd:YAG laser (mode-locked or Q-switched) intended for

posterior capsulotomy. On February 20, 1986, the MLMA amended its

petition to include section 513(f)(2) of the act and 21 CFR 860.134 of

the regulations as a basis for its requested relief. The petition

requested that the ophthalmic Nd:YAG laser (mode-locked or Q-switched),

intended for posterior capsulotomy, be reclassified from class III into

class II. FDA referred the petition to the Panel for its recommendation

as to whether the device should be reclassified. On May 22, 1986,

during an open public meeting the Panel recommended that FDA reclassify

the device from class III into class II when intended for use in

posterior capsulotomy. The Panel identified the following devices as

examples of the generic type of device: The Meditec OPL-3, the M-Tec

2000, the Horizon 2000, the Horizon 2500, and the YAG-100.

The Panel also recommended that this generic type of device be

identified as the ``Nd:YAG laser for posterior capsulotomy.'' On

December 14, 1987 (52 FR 47454), FDA published in the Federal Register

a notice announcing the Panel's recommendation. On March 31, 1988, FDA

ordered (by letter to MLMA) the reclassification of the Nd:YAG laser

intended for posterior capsulotomy and substantially equivalent devices

of this generic type from class III into class II.

On March 2, 1993, ISL submitted to FDA, under section 513(f) of the

act, a petition requesting reclassification of the ophthalmic Nd:YAG

laser (mode-locked or Q-switched) intended for peripheral iridotomy

from class III into class II (Ref. 1). The agency referred the petition

to the Panel for its recommendation on the requested change in

classification.

III. Recommendation of the Panel

The Panel met on October 28, 1993, in an open public meeting to

discuss the subject device. After considering the published studies,

published data on laser parameters for safe and effective Nd:YAG

iridotomy, and the guidelines for laser iridotomy published by the

American Academy of Ophthalmology (Ref. 2), the Panel recommended that

the ophthalmic Nd:YAG laser (mode-locked or Q-switched) intended for

peripheral iridotomy be reclassified from class III into class II. The

Panel believed the petitioners had presented sufficient data to

demonstrate that special controls can be established to provide

reasonable assurance of the safety and effectiveness of the device for

its intended use. The Panel also noted that the procedure is well

understood and widely used by most ophthalmologists in the United

States, as evidenced by the discussion of the Panel members (Ref. 3 p.

83).

IV. Device Description

The ophthalmic Nd:YAG laser intended for peripheral iridotomy

consists of a mode-locked or Q-switched solid state Nd:YAG laser that

generates short pulse, low energy, high power, coherent optical

radiation. When the laser output is combined with focusing optics, the

high irradiance at the target site causes tissue disruption via optical

breakdown. A visible aiming system is utilized to target the invisible

Nd:YAG laser radiation on or in close proximity to the target tissue.

A. Principles of Operation

The Nd:YAG laser is one component of a device system that also

includes conditioning optics, a delivery system, an aiming system, and

operator controls. Its laser beam must be shaped by conditioning optics

to a configuration with a specific profile and desired characteristics.

The physical properties of the Nd:YAG laser beam that directly

influence the ability of the device to perform its intended function

safely and effectively are its invisible infrared beam at a wavelength

of 1,064 nanometers, output pulse generating method, output energy,

pulse width, spatial mode, convergence angle, spotsize, and pulse

repetition frequency. The only variable that is selected by the

ophthalmic surgeon during the iridotomy procedure is the device's

output energy.

While other types of lasers (e.g., the argon laser) used for

ophthalmic surgery employ long duration exposures to achieve thermal

tissue effects for photocoagulation, tissue cutting, or tissue

destruction, the ophthalmic Nd:YAG laser (mode-locked or Q-switched)

intended for peripheral iridotomy uses very short duration exposures

(pulses) that are focused precisely to small spot sizes and that

produce a high local irradiance (power density). The combination of

short exposure duration and high irradiance results in nonlinear

absorption of the radiation by the target tissue, causing tissue

disruption through optical breakdown. The plasma generated by the

process of optical breakdown provides protection for posterior tissue

in direct line with the incident beam. These unique characteristics

permit the ophthalmic Nd:YAG laser to perform a patent iridotomy with

reduced inflammation, regardless of iris pigmentation.

B. Device Specifications

Mode-locked laser output consists of a train of 7 to 10 pulses with

a pulse duration of about 30 nanoseconds and a pulsewidth of about 30

picoseconds. Q-switched laser output consists of single pulses, with

pulsewidths of about 2 to 20 nanoseconds in duration.

[[Page 9375]]

The typical threshold of optical breakdown of tissue in air for

mode-locked lasers is 1014 watts per centimeter squared, and for

Q-switched lasers is 1011 watts per centimeter squared. The

threshold for optical breakdown of tissue in an aqueous environment

appears to be lower but varies depending upon the nature of the tissue.

For disruption of the iris of the eye, an energy setting of 4.0 to 6.0

millijoules results in optical breakdown creating the desired tissue

effect after application of 1 to 4 bursts that contain 1 to 4 pulses/

burst (Refs. 10, 11, 12, 13, 14, and 15).

In addition to the laser, the other two main components of the

system subject to the petition are a visible light beam aiming system

and a slit-lamp biomicroscope used by the operator to target the

treatment laser beam and to visually monitor the treatment process.

V. Summary of Reasons for the Recommendation

The Panel based its recommendation on the data and information

contained in the petition and presented during the open committee

discussion during the Panel meeting on October 28, 1993. After review

and consideration of the available information, the Panel gave the

following reasons in support of its recommendation to reclassify the

generic type ophthalmic Nd:YAG laser (mode-locked or Q-switched)

intended for peripheral iridotomy from class III into class II:

(1) The device is not an implant.

(2) General controls by themselves are insufficient to provide

reasonable assurance of the safety and effectiveness of the device.

(3) There is sufficient publicly available information to establish

special controls to assure the performance of the device for its

intended use. Also, there is sufficient publicly available information

to demonstrate that the risks to health have been determined, and that

the relationship between the device's performance parameters and risks

and its safety and effectiveness have been established by valid

scientific evidence.

(4) Various safety features of medical lasers are already

controlled by existing FDA standards (21 CFR 1040.10 and 1040.11)

promulgated under the Radiation Control for Health and Safety Act of

1968 (42 U.S.C. 263b).

The Panel believed that the following devices identified in the

petition are representative of the generic type of device: the NIDEK

YAG-100; the NIDEK 200; the Coherent 9900; and the Meridian LASAG MR-2.

VI. Risks To Health

Based on publicly available information establishing that it can

successfully perform a discission of the iris (iridotomy), the Panel

concluded that the ophthalmic Nd:YAG laser (mode-locked or Q-switched)

intended for peripheral iridotomy is effective for its intended use.

The Panel also determined that the foreseeable risks to health

associated with the device are related to either unintentional damage

to nontarget tissue or postoperative complications resulting from user

error or device malfunction. These risks include corneal damage or

edema, iritis, corectopia, lenticular opacities, retinal damage,

transient elevation of IOP, failure to obtain iridotomy, precipitation

of angle-closure attack, late closure of iridotomy, and iris atrophy.

The risks of these adverse effects have been documented to be low and

acceptable when the device is used in accordance with its directions

and appropriate postoperative care is followed.

The use of the Nd:YAG laser for peripheral iridotomy may be

contraindicated for patients without a clear cornea or aqueous,

patients with chronic uveitis, patients with a tendency to bleed,

patients on anticoagulant therapy, and patients with a glass

intraocular lens.

VII. Summary of Data Upon Which the Recommendation is Based

During its review and discussion of the petition, the Panel paid

close attention to the risks associated with the use of the device. The

clinical studies included in the petition reported few risks to health,

and the few that were reported were clearly identified. The Panel

concluded that special controls can be established to provide

reasonable assurance of the safety and effectiveness of the device when

intended for peripheral iridotomy. The incidence rates of iridotomy

closure, vision loss due to progression of laser induced lens or

corneal damage, additional filtration surgery, transient iris bleeding,

transient IOP spike, focal lens opacities, nonprogressive corneal

endothelial changes, retinal damage, focal corneal opacities, mild

iritis, and hyphema associated with Nd:YAG laser iridotomy are either

lower than those for argon laser surgery or conventional surgical

iridotomy or are self-limiting and not persistent.

Del Priore, et al. (Ref. 4) compared iridotomies using the Nd:YAG

laser and argon laser in a prospective, randomized clinical study. The

study focused on 43 patients (86 eyes) followed for 20 months (mean

followup time 27 7 months). The mean preoperative visual

acuity in the argon treated and the Nd:YAG treated eyes was 6/12

3 Snellen lines and did not change postoperatively. No

retinal detachments or laser burns of the macula were detected.

Iridotomy closure was not observed in any of the Nd:YAG laser treated

eyes, but 9 (21 percent) argon iridotomies required retreatment. Visual

loss due to progression of laser induced lens or corneal damage was not

observed in any eye. Nine of 43 (21 percent) argon laser treated eyes

and 8 of 43 (19 percent) Nd:YAG laser treated eyes required laser

trabeculoplasty for further intraocular pressure lowering after

iridotomy. Transient iris bleeding was encountered in 19 (44 percent)

Nd:YAG laser treated eyes, but was not seen in any argon treated eyes.

Six (32 percent) of the eyes with transient bleeding had IOP elevations

greater than 10 millimeters (mm) Hg within the first 3 hours, and the

IOP spike was greater than 20 mm Hg in four (17 percent) of these eyes.

Focal opacification of the anterior lens capsule was seen in 23 (53

percent) argon laser treated eyes and none of the Nd:YAG laser treated

eyes. This difference is statistically significant (P<0.01). Focal

corneal endothelial opacities were encountered in 13 (30 percent)

Nd:YAG laser treated and 11 (26 percent) argon laser treated eyes.

Neither type of opacity enlarged clinically, and both tended to

regress. Clinically significant corneal edema or corneal decompensation

did not develop in the eyes of either treatment group during long term

followup. Although several different Nd:YAG lasers (AM YAG-100

(American Medical Optics), Coherent JK Nd:YAG, and Coherent 9900) were

used in the study, no differences were indicated by the results. The

Nd:YAG laser offers intraoperative advantages in patients who cannot

maintain a steady head position and fixation, and is independent of

iris color. The Nd:YAG laser is also regarded as the treatment of

choice in most patients with chronic pupillary-block glaucoma (Ref. 4).

In other studies, Fleck, et al. (Ref. 5) compared Nd:YAG laser

iridotomy with and without argon laser pretreatment and concluded that

argon laser pretreatment offers no advantage over primary Nd:YAG laser

iridotomy. On the other hand, Goins, et al. (Ref. 6) found that argon

laser pretreatment significantly reduced the incidence of hemorrhage

during Nd:YAG iridotomy (p=0.012). Robin and Pollack (Ref. 7) found

that hyphema is not clinically significant when eyes are pretreated

with the argon laser. Of the Nd:YAG

[[Page 9376]]

iridotomies they studied, 67 percent (8/12) had operative hemorrhages,

while 17 percent (2/12) of the argon pretreated eyes had hemorrhages.

Robin and Pollack (Ref. 7) also reported a lower incidence of bleeding

when eyes were pretreated with the argon laser. McGalliard and Wishart

(Ref. 8) studied 81 eyes with shallow anterior chambers and raised IOP.

Iridotomies were performed to prevent further angle closure glaucoma

(ACG) and to remove pupillary block that could have contributed to the

raised IOP. In eyes where there was no peripheral anterior synechia

(PAS) there was no drop in IOP, but in eyes with well established PAS

69 percent showed a drop in IOP. Jiang (Ref. 9) also found a very

significant difference between the preoperative values and the

postoperative values at 3-year followup. In a study of 31 patients (40

eyes with persistent angle closure glaucoma (PACG)), the iridotomy

controlled the IOP, and the iridotomy hole closed spontaneously in four

eyes. The success rates were 94 percent at 6 months, 91 percent at 2

years, and dropped to 82.4 percent at the end of the third year.

Romano, et al. (Ref. 10) compared Nd:YAG iridotomy with conventional

surgical iridectomy. They found that in the nonlaser-treated group,

pilocarpine alone controlled the IOP. In the laser treated group, eyes

without PAS required fewer medications to maintain normal pressures

than eyes with PAS required.

Regarding Nd:YAG laser technique, March (Ref. 11) recommends that a

laser lens be used in performing a Nd:YAG laser iridectomy to aid in

the placement of the lesion on the iris. He also recommends iridectomy

placement beneath the upper lid if possible to avoid complications of

halos, blurring, horizontal bands of light, and diplopia secondary to

light transmission through the site postoperatively. Focusing on the

ability of the Nd:YAG laser to produce a patent iridotomy, Spaeth (Ref.

11) reviewed a prospective study of 58 patients in which the right eyes

were treated with the LASAG Microruptor 2 Nd:YAG laser and the left

eyes with a Britt argon laser, and concluded that the Nd:YAG laser can

indeed produce a patent iridotomy. He observed that there was a

significant pressure rise in one third of the cases treated and that

frequent hemorrhage occurred at the time of the iridectomy, but was not

so severe that a gross hyphema developed. In no instance of Nd:YAG

laser treatment was corneal endothelium or anterior lens capsule damage

noted. Completion of the iridectomy was made on the basis of

visualization of the lens through a hole in the iris. The IOP results

reported for both lasers indicated a rise in IOP at 1 hour

postoperative which decreased to the preoperative level 1 week

postoperative.

In two studies by Robin and Pollack (Refs. 7 and 12) using the

Coherent 9900 Q-switched and the AMO YAG-100 lasers, the authors

reported that hyphema was not clinically significant and was consistent

with other studies showing a lower incidence of bleeding for pretreated

argon eyes. In one study, 33 eyes (both brown and blue irises) from 28

patients with pupillary block glaucoma were treated. Study followup was

1 month. Twenty-six had previous argon laser iridectomies. All had

iridectomy closure within a week of argon treatment or there had been

failure to penetrate the iris; the preoperative IOP range was 8 mm to

74 mm Hg and was 10 mm to 43 mm Hg at 1-month followup. Complications

reported after use of the Coherent 9900 Q-switched Nd:YAG laser were

focal discrete nonprogressive corneal endothelial changes in six eyes

(18 percent), bleeding in 12 eyes (36 percent), and IOP greater than 10

mm Hg during the first 3 hours postoperatively in nine eyes (27

percent). No hyphema, laser-induced lens damage or retinal damage was

observed. Two iridectomies closed within days of treatment. Study

followup was 1 month.

In the second study, the authors studied 40 eyes (20 patients) in

which one eye was treated with an argon laser and the fellow eye with a

Q-switched YAG laser, an AMO YAG-100 (7 patients) or a Coherent JK

prototype (13 patients). Iris colors were blue and brown. At no time

was the IOP change significant between the argon laser and YAG laser

treated patients. Inflammation was seen in all patients. Of the argon

treated eyes, 12 had a rise in IOP during the first 3 hours

postoperatively. Six (30 percent) iridectomies required retreatment,

focal corneal opacities were seen in five (25 percent) of the argon

treated eyes, and posterior synechiae were seen in three (15 percent)

of the argon treated eyes. By comparison, thirteen YAG treated eyes had

an IOP rise during the first 3 hours and bleeding occurred in nine (45

percent), with one having less than 5 percent hyphema which cleared by

the first postoperative day. No iridectomy closures were seen, while

focal corneal opacities were seen in seven (35 percent) of the YAG

treated eyes. None of the YAG treated eyes suffered focal lenticular

opacity. Finally, the Panel noted the publication by the American

Academy of Ophthalmology, Laser Peripheral Iridotomy for Pupillary-

Block Glaucoma (Ref. 2), which discusses surgical iridectomy and laser

iridotomy techniques, treatment parameters, complications and patient

care, and provides insight in addressing laser iridotomy and the above

risks.

The Panel believes that the risks identified above that are

directly attributable to the Nd:YAG laser for peripheral iridotomy can

be controlled by special controls. The risks of damage to the corneal

endothelium, the lens, or the retina are slight. These risks can be

minimized by ensuring proper device design of the laser beam for

accuracy and precision. The risk of IOP rise can be controlled by

proper device labeling and by the surgeon through available,

established medical procedures and treatments. There is reasonable

assurance that an ophthalmic Nd:YAG laser (mode-locked or Q-switched)

is safe and effective for iridotomy when the device is used consistent

with appropriate labeling, designed in accordance with proper device

specifications and produced under a quality assurance program to ensure

that critical specifications are met within specified tolerances.

VIII. FDA's Tentative Findings

FDA tentatively concurs with the recommendation of the Panel that

the Nd:YAG laser intended for peripheral iridotomy should be

reclassified into class II and that the generic designation of the

device be changed from Nd:YAG laser for posterior capsulotomy to Nd:YAG

laser for posterior capsulotomy and peripheral iridotomy. The agency

also tentatively concludes that ``new information'' in the form of

publicly available, valid scientific evidence exists to provide

reasonable assurance of the safety and effectiveness of the Nd:YAG

laser for its intended use. Consistent with the purpose of the act,

class II controls (labeling) as defined by section 513(a)(1)(B) of the

act are sufficient to provide reasonable assurance that current Nd:YAG

lasers are safe and effective for their intended use.

IX. Environmental Impact

The agency has determined under 21 CFR 25.24(e)(2) that thisaction

is of a type that does not individually or cumulatively have a

significant effect of the human environment. Therefore, neither as

environmental assessment nor an environmental impact statement is

required.

[[Page 9377]]

X. Analysis of Impacts

FDA has examined the impacts of the proposed rule under Executive

Order 12866 and the Regulatory Flexibility Act (Pub. L. 96-354).

Executive Order 12866 directs agencies to assess all costs and benefits

of available regulatory alternatives and, when regulation is necessary,

to select regulatory approaches that maximize net benefits (including

potential economic, environmental, public health and safety, and other

advantages; distributive impacts; and equity). The agency believes that

this proposed rule is consistent with the regulatory philosophy and

principles identified in the Executive Order. In addition, the proposed

rule is not a significant regulatory action as defined by the Executive

Order and so is not subject to review under the Executive Order.

The Regulatory Flexibility Act requires agencies to analyze

regulatory options that would minimize any significant impact of a rule

on small entities. Because reclassification of devices from class III

into class II may relieve manufacturers of the cost of complying with

the premarket approval requirements in section 515 of the act, and may

permit small potential competitors to enter the marketplace by lowering

their costs, the agency certifies that the final rule will not have a

significant economic impact on a substantial number of small entities.

Therefore, under the Regulatory Flexibility Act, no further analysis is

required.

XI. Request for Comments

Interested persons may, on or before June 6, 1996, submit to the

Dockets Management Branch (address above) written comments regarding

this proposal. Two copies of any comments are to be submitted, except

that individuals may submit one copy. Comments are to be identified

with the docket number found in brackets in the heading of this

document. Received comments may be seen in the office above between 9

a.m. and 4 p.m. Monday through Friday.

XII. References

The following references have been placed on display in the Dockets

Management Branch (address above) and may be seen by interested persons

between 9 a.m. and 4 p.m., Monday through Friday.

1. Reclassification Petition for the Nd:YAG Laser for Iridotomy,

submitted by Intelligent Surgical Lasers, Inc., March 2, 1993.

2. American Academy of Ophthalmology Guideline: Laser Peripheral

Iridotomy for Pupillary-Block Glaucoma, Approved by Board of

Directors, June 25, 1988. (Also contained in the petition.)

3. Transcript of the Ophthalmic Devices Panel Meeting, October

28, 1993.

4. Del Priore, L. V., A. L. Robin, and I. P. Pollack,

``Neodymium:YAG and Argon Laser Iridotomy: Long-term Followup in a

Prospective, Randomized Clinical Trial,'' Ophthalmology, 94(9):1205-

1211, 1988.

5. Fleck, B. W., E. Wright, C. McGlynn, ``Argon Laser

Pretreatment 4 to 6 Weeks Before Nd:YAG Laser Iridotomy,''

Ophthalmic Surgery, 22(11):644-649, 1991.

6. Goins, K., E. Schmeisser, T. Smith, ``Argon Laser in Nd:YAG

Iridotomy,'' Ophthalmic Surgery, 21(7):497-500, 1990.

7. Robin, A. L. and I. P. Pollack, ``Q-switched Neodymium-YAG

Laser Iridotomy in Patients in Whom the Argon Laser Fails,''

Archives of Ophthalmology, 104(4):531-535, 1986.

8. McGalliard, J. N., P. K. Wishart, ``The Effect of Nd:YAG

Iridotomy on Intraocular Pressure in Hypertensive Eyes with Shallow

Anterior Chambers,'' Eye, 4(6):823-829, 1990.

9. Jiang, Y. Q., ``The Long-term Effect of Nd:YAG Laser

Iridotomy,'' Chung-Hua Yn Ko Tsa Chih Chin, Journal of

Ophthalmology, 27(4):221-224, 1991.

10. Romano, J. H., R. A. Hitchings, and D. Pooinasawmy, ``Role

of Nd:YAG Peripheral Iridectomy in the Management of Ocular

Hypertension With a Narrow Angle,'' Ophthalmic Surgery, 19(11):814-

816, 1988.

11. March, W. F., and G. Spaeth, ``YAG Laser Iridectomy,

Complications,'' Ophthalmic Lasers (A Second Generation), Thorogare,

New York: Slack Inc., 1990.

12. Robin, A. L. and I. P. Pollack, ``A Comparison of

Neodymium:YAG and Argon Laser Iridotomies,'' Ophthalmology,

91(9):1011-1016, 1984.

13. Moster, M. R., et al., ``Laser Iridectomy, A Controlled

Study Comparing Argon and Neodymium:YAG,'' Ophthalmology, 93:20-24,

1986.

14. Cinotti, D. J., et al., ``Neodymium:YAG Laser Therapy for

Pseudophakic Pupillary Block,'' Journal of Cataract and Refractive

Surgery, 12:174-179, 1986.

15. Robin, A. L. et al, ``Q-switched Neodymium-YAG Iridotomy: A

Field Trial with a Portable Laser System,'' Archives of

Ophthalmology, 104:526-530, 1986.

List of Subjects in 21 CFR Part 886

Medical devices, Ophthalmic goods and services.

Therefore, under the Federal Food, Drug, and Cosmetic Act and under

authority delegated to the Commissioner of Food and Drugs, it is

proposed that 21 CFR part 886 be amended as follows:

PART 886--OPHTHALMIC DEVICES

1. The authority citation for 21 CFR part 886 continues to read as

follows:

Authority: Secs. 501, 510, 513, 515, 520, 701 of the Federal

Food, Drug, and Cosmetic Act (21 U.S.C. 351, 360, 360c, 360e, 360j,

371).

2. Section 886.4392 is amended by revising the section heading and

paragraph (a) to read as follows:

Sec. 886.4392 Nd:YAG laser for posterior capsulotomy and peripheral-

iridotomy.

(a) Identification. The Nd:YAG laser for posterior capsulotomy and

peripheral iridotomy consists of a mode-locked or Q-switched solid

state Nd:YAG laser intended for disruption of the posterior capsule or

the iris via optical breakdown. The Nd:YAG laser generates short pulse,

low energy, high power, coherent optical radiation. When the laser

output is combined with focusing optics, the high irradiance at the

target causes tissue disruption via optical breakdown. A visible aiming

system is utilized to target the invisible Nd:YAG laser radiation on or

in close proximity to the target tissue.

* * * * *

Dated: February 14, 1996.

D.B. Burlington,

Director, Center for Devices and Radiological Health.

[FR Doc. 96-5445 Filed 3-7-96; 8:45 am]

BILLING CODE 4160-01-F